AROMATASE INHIBITORS – FULL GUIDE FOR HEIGHTMAXXING, PUBERTY DELAY & ESTROGEN CONTROL

[zaebalsya]

@renos Great thread

Could you help me tho
I have e2 42.90 pg/mL and T 40.5 nmol/l. Should I lower my E2 to 20 pg/mL? Or should there be some balance between the amount of estradiol and testosterone?
I'm 185/6'1 at 18,5.
Just wanna reach 188/6'2

 

[renos]

E2 is extremely important for brain health and brain development nonetheless.

im not telling anyone to crash their E2, I'm saying you should keep it around 15-20 pg/mL which is still considered healthy

i will look into the study you sent more

Dad 6'5, I'm 5'9 how do I reach potential??

Lurker here, debut post. Dad - 6'5 Mum - 5'7 Predicted height = ~6'2.5 (male obv) Me - 5'9 @just turned 17 Haven't grown since like fucking 13/14y/o Feels like I won genetic lottery with tall parents but my ticket is invalid or sum shit. I heard stories some people shoot up at 18/19/even...

looksmax.org

in terms of growth plate closure, the androgenic effect of the metabolite is usually not something you should worry about, especially not at a dose of 12,5mg
(from my research, but maybe you know more than i do here)

but i added the part of possible hair loss

Exemestane is harsher on hair because of its androgenic metabolite, 17-β-hydroxyexemestane.
I’d recommend adding something like finasteride if you choose exemestane.
(That said, hair loss from exemestane only happens if you’re genetically prone to it)

 

[renos]

I'm 185/6'1 at 18,5.

not really worth it to hop on anything at 185cm
are your plates open?

 

[zaebalsya]

not really worth it to hop on anything at 185cm
are your plates open?

Yea, still open
185 is great for sure, but I would like to be a little taller cuz I'm actually football goalkeeper

 

[renos]

Yea, still open
185 is great for sure, but I would like to be a little taller cuz I'm actually football goalkeeper

pm me

 

[Stacyslayerᛉ]

nice seeing you to be high iq, my german friend. so if i have gyno, its a sign i can pretty safely take AI, right? and also what do you think aboout the source SSA(sigma audley)

 

[renos]

so if i have gyno, its a sign i can pretty safely take AI, right?

you should still do blood tests

what do you think aboout the source SSA(sigma audley)

their hgh is good, didn't tried anything else tough, but I think for the price, it's the best source out there rn

 

[Stacyslayerᛉ]

you should still do blood tests

their hgh is good, didn't tried anything else tough, but I think for the price, it's the best source out there rn

so your cycling rn? can i ask what your running currently?

 

[renos]

so your cycling rn? can i ask what your running currently?

Just HGH, ordered exemestane, but it didn't arrive jet

I'm already huge asf, so test etc. wouldn't be worth it

 

[Zagro]

Damn already making guides brah looks pretty nice, bookmarked for later and thanks for the mention

 

[nestivv]

When it comes to heightmaxxing people always recommend the combination of HGH and an AI
but what even are Aromatase Inhibitors?

This guide will teach you everything you need to know about Aromatase inhibitors!
read this guide if you want to gain knowledge about HGH → https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

THE ROLE OF ESTROGEN WHEN IT COMES TO HEIGHT
Human linear growth occurs at the epiphyseal (growth) plates of long bones, which are zones of cartilage undergoing endochondral ossification.
These plates consist of:
Resting zone: reserves of chondrocytes
Proliferative zone: active cell division
Hypertrophic zone: cell enlargement and mineralization

View attachment 4004032
So, bone lengthening continues until the growth plate closes, which marks the end of height increase.
This closure process is triggered by estrogen
How?
Estrogen closes growth plates by binding to estrogen receptor alpha on chondrocytes, pushing them to mature faster while depleting the reserve of stem-like cells that keep the plate active once these cells mature too quickly, the growth plate runs out of new cells that can make more bone length.

Estrogen also makes the plate release signals that pull in blood vessels, which bring bone building cells
These cells replace the last bits of cartilage with solid bone.
When that happens, the growth plate turns into a thin bony line, and you can’t get any taller.

So make sure your plates are open before you take action
you can confirm this through an x-ray of your hand or knee

Spoiler: open vs closed growth plates

View attachment 4008423

The younger your bone age, the more potential you have to grow
ideally it should be younger than 16, but even after that you could grow a few more cm

but once plates are closed, Limb lenghtening is the only way to increase height other than fixing posture and wearing shoe-lifts

WHAT ARE AROMATASE INHIBITORS?

Spoiler: history

The story starts back in the 1950s and 60s when scientists first figured out how estrogen is made in the body.
They realized that if you could block the aromatase enzyme, you could lower estrogen levels and potentially slow down some type of cancers

In the 1970s, the first aromatase inhibitors were developed. These early drugs, like aminoglutethimide, weren’t very selective and had a lot of side effects.
They worked by binding tightly to the enzyme and basically breaking it, but because they weren’t very specific, patients often had issues.

Then, during the 1980s and early 90s, researchers worked on making better inhibitors.
Nonsteroidal ones came along, such as fadrozole and vorozole, which were safer and more targeted.

The big breakthrough happened in the 1990s: anastrozole, letrozole, and exemestane were invented
These drugs were more effective, had fewer side effects, and became the new standard treatment for hormone-sensitive breast cancer
They’re still widely used today because they work well and patients tolerate them better than older drugs.

Aromatase inhibitors also come to play for treating male hypogonadism or delaying puberty
(and with that being able to grow for a longer period of time)

Aromatase inhibitors are compounds that block or kill the enzyme aromatase, which converts testosterone into estrogen.

Spoiler: what is aromatase

Aromatase is a cytochrome P450 enzyme, encoded bythe CYP19A1 gene.
It catalyzes the aromatization of the A-ring ofandrogens, specifically:
Testosterone into Estradiol and Androstenedione intoEstrone

(Estrogen refers to a group of hormones that include estradiol, estrone, and estriol, with estradiol being the most potent and prevalent)

By lowering estrogen levels, AIs can delay epiphyseal fusion, extending the window for longitudinal bone growth

The Aromatization Reaction (Biochemistry)
At the molecular level, aromatase performs a three-stepoxidation of the androgen substrate’s A-ring:
Hydroxylation of the 19-methyl group (C19).
Conversion to a formyl group.
Aromatization of the A-ring, forming an aromaticphenol (the hallmark of estrogen).

This process is NADPH-dependent, and localiezd in the endoplasmic reticulum of cells
By taking an aromatase inhibitor we can block this process leading to less estrogen

ANASTROZOLE, LETROZOLE AND EXEMESTANE IN COMPARISON
The main difference is that anastrozole and letrozole are non-steroidal aromatase inhibitors, while exemestane is a steroidal aromatase inhibitor.
Simply put, this means that anastrozole and letrozole anesthetize the aromatase enzyme while exemestane kills the aromatase enzyme
(The enzyme is reproduced by the body)

GENERAL COMPARISON​

Property	Anastrozole (Arimidex)	Letrozole (Femara)	Exemestane (Aromasin)
Type	Non-steroidal, reversible	Non-steroidal, reversible	Steroidal, irreversible
Estrogen Suppression	~50–70% (dose dependent)	~80–98% (very potent)	~65–85% (irreversible)
Half-Life	~48 hrs	~40–60 hrs	~24–27 hrs
Rebound Risk	Medium if stopped fast	High (sharp increase)	Low (enzyme destroyed)
Titration Precision	High (easy microdose)	Moderate to difficult	Low (fixed dose tabs)
Bone Impact	Mild (long-term)	moderate to severe	moderate
Lipid impact	Mild, but could affect HDL	Moderate to severe	moderate
Onset of Suppression	~24 hours	Within hours	~24 hours (stronger than Anastrozole)
Peak Suppression	~2–4 days	~2–3 days	~2–3 days

PRICES​

Source	Anastrozole Price (1mg)	Letrozole Price (2.5mg)	Exemestane Price (25mg)
Pharma (Brand)	$5–$10	$8–$15	$10–$20
Generic (Indian)	$0.50–$1.50	$1–$3	$1–$4
UGL (Chinese)	$0.20–$0.50	$0.30–$1	$0.30–$1

SIDE EFFECTS​

Side Effect	Anastrozole (Arimidex)	Letrozole (Femera)	Exemestane (Aromasin)
Hot flashes	Common	Common	Common
Joint pain	Moderate	Moderate to severe	Mild to moderate
Fatigue	Mild to moderate	Moderate	Mild to moderate
Bone density loss	Mild (long-term use)	More severe if misused	Moderate (monitor needed)
Nausea	Mild	Mild to moderate	Mild
Mood changes	Possible	Possible	Possible
Headache	Occasionally	Occasionally	Occasionally
Increased cholesterol	Mild	Moderate to severe	Moderate
Muscle pain	Mild	Moderate	Mild

Exemestane is harsher on hair because of its androgenic metabolite, 17-β-hydroxyexemestane.
I’d recommend adding something like finasteride if you choose exemestane.
(That said, hair loss from exemestane only happens if you’re genetically prone to it)

Side effects like losing cognitive abilities only occur when your estrogen is under 10 pg/mL for a longer period of time
this and hair loss were the side effects I was afraid of the most, but as long as you know what youre doing, you don't have to worry about them

Here is a study that proves Ais are safe when it comes to influencing cognitive abilities
STUDY https://pubmed.ncbi.nlm.nih.gov/20421333

Also, Ais can increase levels of endogenous Testosterone production in men by 30-60% which is a lot

The biggest downside of non-steroidal Ai's is the possible estrogen rebound

Spoiler: estrogen rebound explained

Estrogen rebound is a phenomenon that occurs when the body experiences an increase in estrogen levels after discontinuing or reducing the dosage of aromatase inhibitors like Anastrozole or Letrozole.

This rebound effect happens because these AIs suppress the production of estrogen, but once the AI is stopped, estrogen levels rise temporarily as the body's natural production resumes.

This abrupt rise in the body’s natural production of estrogen could lead to premature closure of growth plates, potentially impacting final height.

Missing a few doses of a non-steroidal Aromatase Inhibitors could cause that, so be careful when using one
rebound can be strongly reduced by tapering off slowly instead of stopping suddenly

but in comparison to exemestane, letrozole and Anastrozole are cheaper and better studied

My personal choice is Exemestane, because it has the least side effects and estrogen rebound isn't a thing
(but like I said, every AI works, just keep E2 at 15-20 pg/mL
and if youre using a non-steroidal one, be careful that you dont forget to take them)

DOSAGE PROTOCOLS AND BLOODWORK
Test your E2 to find the dosage you probably need
1 week into your Ai you should do another blood test to see if you should adjust the dose
You want to Target blood estradiol levels of 15–20 pg/mL and never go under 10 pg/mL
(for reference, normal estradiol levels for teenagers are around 20-50 pg/mL)

If you can't do blood tests, youre basically playing russian roulette, so be careful
in that scenario start a low dose, for example 6,25mg of Exemestane and adjust the dose slowly on how you feel and symptoms you experience

symptoms of low estrogen
Sudden joint pain/dryness
Drop in libido or morning erections
Brain fog, mood drop, irritability
Dry skin or hair shedding increase
Unexplained fatigue
if these occure, lower the dose immediately

symptoms of high estrogen
Puffy face/water retention
Fat gain on hips/chest
Gynecomastia or nipple sensitivity
Emotional volatility or crying easily
Chronic bloating
if these occure you should up the dose

Also, here is an overview, how much different dosages suppress your estrogen

Spoiler: suppression of estrogen

Anastrozole:
0.5 mg → ~50–60% E2 suppression
1 mg → ~80–85% E2 suppression
5 mg → ~85–90% E2 suppression (plateau)
Letrozole:
0.25 mg → ~60–65% E2 suppression
0.5 mg → ~75–80% E2 suppression
1 mg → ~85–90% E2 suppression
2.5 mg → ~90–95% E2 suppression
Exemestane:
6.25 mg → ~30–35% E2 suppression
12.5 mg → ~55–60% E2 suppression
25 mg → ~85–95% E2 suppression

Avoid over suppression (estrogen crash) and Monitor symptoms and do bloodwork.

BlOODWORK
(budget friendly)

Spoiler: Bloodwork - what to test

Test Estradiol (E2)
Why: Directly shows if your estrogen is in your target range (~15–20 pg/ml).
When:
before the start to calculate the dose you need and then check again 1 week after the start
If everything is correct check 1 month later to see if its stable
then every 8-10 weeks
Total Testosterone + Free Testosterone
Why: AI can raise testosterone; high T can cause secondary effects (acne, aggression, libido swings).
When: Same time as E2 checks.

SHBG (Sex Hormone Binding Globulin)
Why: AI-induced changes in T and E2 affect SHBG, which changes free T availability.
When: every 8-12 weeks Alongside T/E2 checks.

Lipid Panel (Total Cholesterol, LDL, HDL, Triglycerides)
Why: Low E2 can lower HDL and raise LDL → cardiovascular risk.
When: Every 3 months.

Liver Enzymes (ALT, AST)
Why: Ais is metabolized in the liver; rare but possible liver stress.
When: Every 3 months or if symptoms appear.
(important if you drink alcohol)

Bone Health (long-term)
Why: Chronically low E2 can reduce bone density.
When: DEXA scan after 12+ months if running AI long-term.
(optional, but would be good)

simply put together

the baseline test would be:
E2 (sensitive), Total T, Free T, SHBG, Lipid Panel, ALT/AST

around 1 week after AI start:
E2 (sensitive) (optional Total T)

then E2 (sensitive), Total T, Free T, SHBG
every 8-10 weeks and lipids + liver enzymes every 3 months

You can do blood tests in private labs

IMPORTANT NOTES AND TIPS
The time when you take your Ai is not important (should still be around the same time)
But taking your Ai with a meal is
(alternatively, you can take your ai with a tablespoon of olive oil)

Storage:
Dry location with an ideal temperature of 15–25°C and no sun exposure
(just put it in your drawer)

Hormones return to baseline within 2–4 weeks after you stop taking your ai

weird, but don't eat Grapefruits and don't drink Grapefruit Juice
Grapefruit and its juice contain compounds that block the liver enzyme CYP3A4, which helps break down many drugs, including aromatase inhibitors.
This blockage can cause the ai to build up in your blood, and with that increase the risk of side effects

CLINICAL STUDIES OF HEIGHT INCREASE WITH AIS
View attachment 4005487
STUDY https://ijpeonline.biomedcentral.com/articles/10.1186/1687-9856-2015-4

Aromatase inhibitors Alone
Boys with idiopathic short stature or delayed puberty treated with anastrozole (AI) showed around 5 cm increase in predicted adult height by delaying growth plate closure
STUDY https://pubmed.ncbi.nlm.nih.gov/16189252

Growth Hormone (HGH) Alone:
This study looked at kids with idiopathic short stature (ISS), meaning normal GH levels but short height.
HGH treatment increased adult height by an average of 4–6 cm compared to untreated children.
STUDY https://umraniyepediatri.com/storage/upload/pdfs/1732279204-en.pdf

Combination Therapy (AI + HGH):
combining growth hormone with aromatase inhibitors in adolescent boys with idiopathic short stature led to an average adult height increase of about 6 to 9 cm.
STUDY https://academic.oup.com/jcem/article/110/9/e2871/8125692?login=false

HOPEFUL
Boys grow 2.13 cm in average after the age of 18 without anything
a study shows, that on average, boys grew an additional 2.13 cm between ages 18 and 27, with some increasing by as much as 7 cm
absolutely hopeful study
STUDY https://pubmed.ncbi.nlm.nih.gov/6638938

AIS IN CONTEXT OF BODYBUILDING
View attachment 4007910
i dont want this topic to be left out completely, but i will just cover the most important things

because of higher testosterone levels, the body converts more testosterone to estrogen
Ais can help to control estrogen levels during steroid cycles,
preventing side effects like water retention, bloating, and gynecomastia.

They’re used to maintain a healthy testosterone-to-estrogen balance, which supports better muscle gains, mood, and overall performance.
Additionally, by limiting estrogen, AIs can reduce fat storage and help bodybuilders achieve a leaner, more defined physique.

When Ais come to play in bodybuilding
if your Estradiol is too high and you experience side effects like
-Gyno
-Water retention
-Severe acne
-Mood swings (irritability or depression)

At High Doses or for Estrogen-Sensitive Users
some users don't need one even with +500 mg test a week
while some require an AI even with just 250 mg/week
(At ~500 mg testosterone a week most need an AI)

During Contest Prep
Ais reduce water retention, many bodybuilders use that to achieve a more defined and dryer look

Post-Cycle therapy (PCT)
After a steroid cycle to restore natural testosterone production
Often combined with SERMs (Clomid, Nolvadex)

SPECIAL TOPICS
AI Resistance
true resistance to aromatase inhibitors in men is very rare, but possible
In bodybuilding “resistance” usually means underdosing,
poor absorption of the product, or genetic differences in aromatase activity

In practice:
If estrogen stays high despite seemingly adequate AI dosing,
first rule out fake/underdosed product and high androgen load before assuming true resistance

Many UGL AIs are underdosed
Buy from tested sources (Janoshik reports).
and see how much impact they have on your E2 via bloodwork

Myths about estrogen
Myth 1: “Lower estrogen = more muscle gains.”
Truth: Too little estrogen impairs strength, recovery, joint health, and IGF-1 signaling, all critical for muscle growth.

Myth 2: “Estrogen is bad for men and should be eliminated completely.”
Truth: Estrogen plays important roles in men, including bone haelth, brain function, and regulating libido

Myth 3: “If you don’t feel symptoms, your estrogen is fine.”
Truth: Some people have no noticeable symptoms until E2 is way out of range, that's why blood tests are so important
(for example, my E2 was at 56 pg/mL and i didn't notice anything)

CONCLUSION

Spoiler: conclusion

Ais work by lowering estrogen, which delays the closing of your growth plates, giving you more time to grow taller and with that
are a great tool that could give you another 1-6cm, depending on your bone age

(keep in mind that if youre 5'7 at 16 or older with a similar bone age, nothing except LL will bring you to 6'0)

The younger your bone age, the more you can grow trough all of this

even tough they are different, the type of Ai you use doesnt really matter
but understanding how they work does

So, while AIs can help extend your growth window, they’re not some magic pill, get your bloodwork done and dont be a retard

if i forget anything you want to know, just tell me

other threads i strongly recommend reading

Spoiler: threads

Another guide on HGH + Ai
https://looksmax.org/threads/theore...omatase-inhibitor-for-pubertymaxxing.1061735/

Heightmaxxing experience with HGH + Ai
https://looksmax.org/threads/coveri...xperience-results-tips-and-struggles.1172898/

About HGH
https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

hope we all ascend
-renos

Spoiler: tags

@Zagro @Mainlander @MyDreamIsToBe183CM

​

 

[renos]

Damn already making guides brah looks pretty nice, bookmarked for later and thanks for the mention

Wanted to do something like this for long, but I had no knowledge.

I made a guide about fragrances, back then, but now I want to share my knowledge in more requested topics like this.

In general, there’s still a lot I have to learn and want to know, but im learning and educating myself everyday

I Hope that one day I can leave all this shit behind

 

[renos]

@emeraldglass @Gengar @Orc @Randomized Shame

 

[renos]

@Volksstaffel

 

[Deleted member 2461]

When it comes to heightmaxxing people always recommend the combination of HGH and an AI
but what even are Aromatase Inhibitors?

This guide will teach you everything you need to know about Aromatase inhibitors!
read this guide if you want to gain knowledge about HGH → https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

THE ROLE OF ESTROGEN WHEN IT COMES TO HEIGHT
Human linear growth occurs at the epiphyseal (growth) plates of long bones, which are zones of cartilage undergoing endochondral ossification.
These plates consist of:
Resting zone: reserves of chondrocytes
Proliferative zone: active cell division
Hypertrophic zone: cell enlargement and mineralization

View attachment 4004032
So, bone lengthening continues until the growth plate closes, which marks the end of height increase.
This closure process is triggered by estrogen
How?
Estrogen closes growth plates by binding to estrogen receptor alpha on chondrocytes, pushing them to mature faster while depleting the reserve of stem-like cells that keep the plate active once these cells mature too quickly, the growth plate runs out of new cells that can make more bone length.

Estrogen also makes the plate release signals that pull in blood vessels, which bring bone building cells
These cells replace the last bits of cartilage with solid bone.
When that happens, the growth plate turns into a thin bony line, and you can’t get any taller.

So make sure your plates are open before you take action
you can confirm this through an x-ray of your hand or knee

Spoiler: open vs closed growth plates

View attachment 4008423

The younger your bone age, the more potential you have to grow
ideally it should be younger than 16, but even after that you could grow a few more cm

but once plates are closed, Limb lenghtening is the only way to increase height other than fixing posture and wearing shoe-lifts

WHAT ARE AROMATASE INHIBITORS?

Spoiler: history

The story starts back in the 1950s and 60s when scientists first figured out how estrogen is made in the body.
They realized that if you could block the aromatase enzyme, you could lower estrogen levels and potentially slow down some type of cancers

In the 1970s, the first aromatase inhibitors were developed. These early drugs, like aminoglutethimide, weren’t very selective and had a lot of side effects.
They worked by binding tightly to the enzyme and basically breaking it, but because they weren’t very specific, patients often had issues.

Then, during the 1980s and early 90s, researchers worked on making better inhibitors.
Nonsteroidal ones came along, such as fadrozole and vorozole, which were safer and more targeted.

The big breakthrough happened in the 1990s: anastrozole, letrozole, and exemestane were invented
These drugs were more effective, had fewer side effects, and became the new standard treatment for hormone-sensitive breast cancer
They’re still widely used today because they work well and patients tolerate them better than older drugs.

Aromatase inhibitors also come to play for treating male hypogonadism or delaying puberty
(and with that being able to grow for a longer period of time)

Aromatase inhibitors are compounds that block or kill the enzyme aromatase, which converts testosterone into estrogen.

Spoiler: what is aromatase

Aromatase is a cytochrome P450 enzyme, encoded bythe CYP19A1 gene.
It catalyzes the aromatization of the A-ring ofandrogens, specifically:
Testosterone into Estradiol and Androstenedione intoEstrone

(Estrogen refers to a group of hormones that include estradiol, estrone, and estriol, with estradiol being the most potent and prevalent)

By lowering estrogen levels, AIs can delay epiphyseal fusion, extending the window for longitudinal bone growth

The Aromatization Reaction (Biochemistry)
At the molecular level, aromatase performs a three-stepoxidation of the androgen substrate’s A-ring:
Hydroxylation of the 19-methyl group (C19).
Conversion to a formyl group.
Aromatization of the A-ring, forming an aromaticphenol (the hallmark of estrogen).

This process is NADPH-dependent, and localiezd in the endoplasmic reticulum of cells
By taking an aromatase inhibitor we can block this process leading to less estrogen

ANASTROZOLE, LETROZOLE AND EXEMESTANE IN COMPARISON
The main difference is that anastrozole and letrozole are non-steroidal aromatase inhibitors, while exemestane is a steroidal aromatase inhibitor.
Simply put, this means that anastrozole and letrozole anesthetize the aromatase enzyme while exemestane kills the aromatase enzyme
(The enzyme is reproduced by the body)

GENERAL COMPARISON​

Property	Anastrozole (Arimidex)	Letrozole (Femara)	Exemestane (Aromasin)
Type	Non-steroidal, reversible	Non-steroidal, reversible	Steroidal, irreversible
Estrogen Suppression	~50–70% (dose dependent)	~80–98% (very potent)	~65–85% (irreversible)
Half-Life	~48 hrs	~40–60 hrs	~24–27 hrs
Rebound Risk	Medium if stopped fast	High (sharp increase)	Low (enzyme destroyed)
Titration Precision	High (easy microdose)	Moderate to difficult	Low (fixed dose tabs)
Bone Impact	Mild (long-term)	moderate to severe	moderate
Lipid impact	Mild, but could affect HDL	Moderate to severe	moderate
Onset of Suppression	~24 hours	Within hours	~24 hours (stronger than Anastrozole)
Peak Suppression	~2–4 days	~2–3 days	~2–3 days

PRICES​

Source	Anastrozole Price (1mg)	Letrozole Price (2.5mg)	Exemestane Price (25mg)
Pharma (Brand)	$5–$10	$8–$15	$10–$20
Generic (Indian)	$0.50–$1.50	$1–$3	$1–$4
UGL (Chinese)	$0.20–$0.50	$0.30–$1	$0.30–$1

SIDE EFFECTS​

Side Effect	Anastrozole (Arimidex)	Letrozole (Femera)	Exemestane (Aromasin)
Hot flashes	Common	Common	Common
Joint pain	Moderate	Moderate to severe	Mild to moderate
Fatigue	Mild to moderate	Moderate	Mild to moderate
Bone density loss	Mild (long-term use)	More severe if misused	Moderate (monitor needed)
Nausea	Mild	Mild to moderate	Mild
Mood changes	Possible	Possible	Possible
Headache	Occasionally	Occasionally	Occasionally
Increased cholesterol	Mild	Moderate to severe	Moderate
Muscle pain	Mild	Moderate	Mild

Exemestane is harsher on hair because of its androgenic metabolite, 17-β-hydroxyexemestane.
I’d recommend adding something like finasteride if you choose exemestane.
(That said, hair loss from exemestane only happens if you’re genetically prone to it)

Side effects like losing cognitive abilities only occur when your estrogen is under 10 pg/mL for a longer period of time
this and hair loss were the side effects I was afraid of the most, but as long as you know what youre doing, you don't have to worry about them

Here is a study that proves Ais are safe when it comes to influencing cognitive abilities
STUDY https://pubmed.ncbi.nlm.nih.gov/20421333

Also, Ais can increase levels of endogenous Testosterone production in men by 30-60% which is a lot

The biggest downside of non-steroidal Ai's is the possible estrogen rebound

Spoiler: estrogen rebound explained

Estrogen rebound is a phenomenon that occurs when the body experiences an increase in estrogen levels after discontinuing or reducing the dosage of aromatase inhibitors like Anastrozole or Letrozole.

This rebound effect happens because these AIs suppress the production of estrogen, but once the AI is stopped, estrogen levels rise temporarily as the body's natural production resumes.

This abrupt rise in the body’s natural production of estrogen could lead to premature closure of growth plates, potentially impacting final height.

Missing a few doses of a non-steroidal Aromatase Inhibitors could cause that, so be careful when using one
rebound can be strongly reduced by tapering off slowly instead of stopping suddenly

but in comparison to exemestane, letrozole and Anastrozole are cheaper and better studied

My personal choice is Exemestane, because it has the least side effects and estrogen rebound isn't a thing
(but like I said, every AI works, just keep E2 at 15-20 pg/mL
and if youre using a non-steroidal one, be careful that you dont forget to take them)

DOSAGE PROTOCOLS AND BLOODWORK
Test your E2 to find the dosage you probably need
1 week into your Ai you should do another blood test to see if you should adjust the dose
You want to Target blood estradiol levels of 15–20 pg/mL and never go under 10 pg/mL
(for reference, normal estradiol levels for teenagers are around 20-50 pg/mL)

If you can't do blood tests, youre basically playing russian roulette, so be careful
in that scenario start a low dose, for example 6,25mg of Exemestane and adjust the dose slowly on how you feel and symptoms you experience

symptoms of low estrogen
Sudden joint pain/dryness
Drop in libido or morning erections
Brain fog, mood drop, irritability
Dry skin or hair shedding increase
Unexplained fatigue
if these occure, lower the dose immediately

symptoms of high estrogen
Puffy face/water retention
Fat gain on hips/chest
Gynecomastia or nipple sensitivity
Emotional volatility or crying easily
Chronic bloating
if these occure you should up the dose

Also, here is an overview, how much different dosages suppress your estrogen

Spoiler: suppression of estrogen

Anastrozole:
0.5 mg → ~50–60% E2 suppression
1 mg → ~80–85% E2 suppression
5 mg → ~85–90% E2 suppression (plateau)
Letrozole:
0.25 mg → ~60–65% E2 suppression
0.5 mg → ~75–80% E2 suppression
1 mg → ~85–90% E2 suppression
2.5 mg → ~90–95% E2 suppression
Exemestane:
6.25 mg → ~30–35% E2 suppression
12.5 mg → ~55–60% E2 suppression
25 mg → ~85–95% E2 suppression

Avoid over suppression (estrogen crash) and Monitor symptoms and do bloodwork.

BlOODWORK
(budget friendly)

Spoiler: Bloodwork - what to test

Test Estradiol (E2)
Why: Directly shows if your estrogen is in your target range (~15–20 pg/ml).
When:
before the start to calculate the dose you need and then check again 1 week after the start
If everything is correct check 1 month later to see if its stable
then every 8-10 weeks
Total Testosterone + Free Testosterone
Why: AI can raise testosterone; high T can cause secondary effects (acne, aggression, libido swings).
When: Same time as E2 checks.

SHBG (Sex Hormone Binding Globulin)
Why: AI-induced changes in T and E2 affect SHBG, which changes free T availability.
When: every 8-12 weeks Alongside T/E2 checks.

Lipid Panel (Total Cholesterol, LDL, HDL, Triglycerides)
Why: Low E2 can lower HDL and raise LDL → cardiovascular risk.
When: Every 3 months.

Liver Enzymes (ALT, AST)
Why: Ais is metabolized in the liver; rare but possible liver stress.
When: Every 3 months or if symptoms appear.
(important if you drink alcohol)

Bone Health (long-term)
Why: Chronically low E2 can reduce bone density.
When: DEXA scan after 12+ months if running AI long-term.
(optional, but would be good)

simply put together

the baseline test would be:
E2 (sensitive), Total T, Free T, SHBG, Lipid Panel, ALT/AST

around 1 week after AI start:
E2 (sensitive) (optional Total T)

then E2 (sensitive), Total T, Free T, SHBG
every 8-10 weeks and lipids + liver enzymes every 3 months

You can do blood tests in private labs

IMPORTANT NOTES AND TIPS
The time when you take your Ai is not important (should still be around the same time)
But taking your Ai with a meal is
(alternatively, you can take your ai with a tablespoon of olive oil)

Storage:
Dry location with an ideal temperature of 15–25°C and no sun exposure
(just put it in your drawer)

Hormones return to baseline within 2–4 weeks after you stop taking your ai

weird, but don't eat Grapefruits and don't drink Grapefruit Juice
Grapefruit and its juice contain compounds that block the liver enzyme CYP3A4, which helps break down many drugs, including aromatase inhibitors.
This blockage can cause the ai to build up in your blood, and with that increase the risk of side effects

CLINICAL STUDIES OF HEIGHT INCREASE WITH AIS
View attachment 4005487
STUDY https://ijpeonline.biomedcentral.com/articles/10.1186/1687-9856-2015-4

Aromatase inhibitors Alone
Boys with idiopathic short stature or delayed puberty treated with anastrozole (AI) showed around 5 cm increase in predicted adult height by delaying growth plate closure
STUDY https://pubmed.ncbi.nlm.nih.gov/16189252

Growth Hormone (HGH) Alone:
This study looked at kids with idiopathic short stature (ISS), meaning normal GH levels but short height.
HGH treatment increased adult height by an average of 4–6 cm compared to untreated children.
STUDY https://umraniyepediatri.com/storage/upload/pdfs/1732279204-en.pdf

Combination Therapy (AI + HGH):
combining growth hormone with aromatase inhibitors in adolescent boys with idiopathic short stature led to an average adult height increase of about 6 to 9 cm.
STUDY https://academic.oup.com/jcem/article/110/9/e2871/8125692?login=false

HOPEFUL
Boys grow 2.13 cm in average after the age of 18 without anything
a study shows, that on average, boys grew an additional 2.13 cm between ages 18 and 27, with some increasing by as much as 7 cm
absolutely hopeful study
STUDY https://pubmed.ncbi.nlm.nih.gov/6638938

AIS IN CONTEXT OF BODYBUILDING
View attachment 4007910
i dont want this topic to be left out completely, but i will just cover the most important things

because of higher testosterone levels, the body converts more testosterone to estrogen
Ais can help to control estrogen levels during steroid cycles,
preventing side effects like water retention, bloating, and gynecomastia.

They’re used to maintain a healthy testosterone-to-estrogen balance, which supports better muscle gains, mood, and overall performance.
Additionally, by limiting estrogen, AIs can reduce fat storage and help bodybuilders achieve a leaner, more defined physique.

When Ais come to play in bodybuilding
if your Estradiol is too high and you experience side effects like
-Gyno
-Water retention
-Severe acne
-Mood swings (irritability or depression)

At High Doses or for Estrogen-Sensitive Users
some users don't need one even with +500 mg test a week
while some require an AI even with just 250 mg/week
(At ~500 mg testosterone a week most need an AI)

During Contest Prep
Ais reduce water retention, many bodybuilders use that to achieve a more defined and dryer look

Post-Cycle therapy (PCT)
After a steroid cycle to restore natural testosterone production
Often combined with SERMs (Clomid, Nolvadex)

SPECIAL TOPICS
AI Resistance
true resistance to aromatase inhibitors in men is very rare, but possible
In bodybuilding “resistance” usually means underdosing,
poor absorption of the product, or genetic differences in aromatase activity

In practice:
If estrogen stays high despite seemingly adequate AI dosing,
first rule out fake/underdosed product and high androgen load before assuming true resistance

Many UGL AIs are underdosed
Buy from tested sources (Janoshik reports).
and see how much impact they have on your E2 via bloodwork

Myths about estrogen
Myth 1: “Lower estrogen = more muscle gains.”
Truth: Too little estrogen impairs strength, recovery, joint health, and IGF-1 signaling, all critical for muscle growth.

Myth 2: “Estrogen is bad for men and should be eliminated completely.”
Truth: Estrogen plays important roles in men, including bone haelth, brain function, and regulating libido

Myth 3: “If you don’t feel symptoms, your estrogen is fine.”
Truth: Some people have no noticeable symptoms until E2 is way out of range, that's why blood tests are so important
(for example, my E2 was at 56 pg/mL and i didn't notice anything)

CONCLUSION

Spoiler: conclusion

Ais work by lowering estrogen, which delays the closing of your growth plates, giving you more time to grow taller and with that
are a great tool that could give you another 1-6cm, depending on your bone age

(keep in mind that if youre 5'7 at 16 or older with a similar bone age, nothing except LL will bring you to 6'0)

The younger your bone age, the more you can grow through all of this

even tough they are different, the type of Ai you use doesnt really matter
but understanding how they work does

So, while AIs can help extend your growth window, they’re not some magic pill, get your bloodwork done and dont be a retard

if i forget anything you want to know, just tell me

other threads i strongly recommend reading

Spoiler: threads

Another guide on HGH + Ai
https://looksmax.org/threads/theore...omatase-inhibitor-for-pubertymaxxing.1061735/

Heightmaxxing experience with HGH + Ai
https://looksmax.org/threads/coveri...xperience-results-tips-and-struggles.1172898/

About HGH
https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

hope we all ascend
-renos

Spoiler: tags

@Zagro @Mainlander @MyDreamIsToBe183CM

​

Dnrd but great work bro

 

[renos]

Dnrd but great work bro

das hat so lange gedauert und ich habe nicht mal sticky bekommen

 

[keife]

When it comes to heightmaxxing people always recommend the combination of HGH and an AI
but what even are Aromatase Inhibitors?

This guide will teach you everything you need to know about Aromatase inhibitors!
read this guide if you want to gain knowledge about HGH → https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

THE ROLE OF ESTROGEN WHEN IT COMES TO HEIGHT
Human linear growth occurs at the epiphyseal (growth) plates of long bones, which are zones of cartilage undergoing endochondral ossification.
These plates consist of:
Resting zone: reserves of chondrocytes
Proliferative zone: active cell division
Hypertrophic zone: cell enlargement and mineralization

View attachment 4004032
So, bone lengthening continues until the growth plate closes, which marks the end of height increase.
This closure process is triggered by estrogen
How?
Estrogen closes growth plates by binding to estrogen receptor alpha on chondrocytes, pushing them to mature faster while depleting the reserve of stem-like cells that keep the plate active once these cells mature too quickly, the growth plate runs out of new cells that can make more bone length.

Estrogen also makes the plate release signals that pull in blood vessels, which bring bone building cells
These cells replace the last bits of cartilage with solid bone.
When that happens, the growth plate turns into a thin bony line, and you can’t get any taller.

So make sure your plates are open before you take action
you can confirm this through an x-ray of your hand or knee

Spoiler: open vs closed growth plates

View attachment 4008423

The younger your bone age, the more potential you have to grow
ideally it should be younger than 16, but even after that you could grow a few more cm

but once plates are closed, Limb lenghtening is the only way to increase height other than fixing posture and wearing shoe-lifts

WHAT ARE AROMATASE INHIBITORS?

Spoiler: history

The story starts back in the 1950s and 60s when scientists first figured out how estrogen is made in the body.
They realized that if you could block the aromatase enzyme, you could lower estrogen levels and potentially slow down some type of cancers

In the 1970s, the first aromatase inhibitors were developed. These early drugs, like aminoglutethimide, weren’t very selective and had a lot of side effects.
They worked by binding tightly to the enzyme and basically breaking it, but because they weren’t very specific, patients often had issues.

Then, during the 1980s and early 90s, researchers worked on making better inhibitors.
Nonsteroidal ones came along, such as fadrozole and vorozole, which were safer and more targeted.

The big breakthrough happened in the 1990s: anastrozole, letrozole, and exemestane were invented
These drugs were more effective, had fewer side effects, and became the new standard treatment for hormone-sensitive breast cancer
They’re still widely used today because they work well and patients tolerate them better than older drugs.

Aromatase inhibitors also come to play for treating male hypogonadism or delaying puberty
(and with that being able to grow for a longer period of time)

Aromatase inhibitors are compounds that block or kill the enzyme aromatase, which converts testosterone into estrogen.

Spoiler: what is aromatase

Aromatase is a cytochrome P450 enzyme, encoded bythe CYP19A1 gene.
It catalyzes the aromatization of the A-ring ofandrogens, specifically:
Testosterone into Estradiol and Androstenedione intoEstrone

(Estrogen refers to a group of hormones that include estradiol, estrone, and estriol, with estradiol being the most potent and prevalent)

By lowering estrogen levels, AIs can delay epiphyseal fusion, extending the window for longitudinal bone growth

The Aromatization Reaction (Biochemistry)
At the molecular level, aromatase performs a three-stepoxidation of the androgen substrate’s A-ring:
Hydroxylation of the 19-methyl group (C19).
Conversion to a formyl group.
Aromatization of the A-ring, forming an aromaticphenol (the hallmark of estrogen).

This process is NADPH-dependent, and localiezd in the endoplasmic reticulum of cells
By taking an aromatase inhibitor we can block this process leading to less estrogen

ANASTROZOLE, LETROZOLE AND EXEMESTANE IN COMPARISON
The main difference is that anastrozole and letrozole are non-steroidal aromatase inhibitors, while exemestane is a steroidal aromatase inhibitor.
Simply put, this means that anastrozole and letrozole anesthetize the aromatase enzyme while exemestane kills the aromatase enzyme
(The enzyme is reproduced by the body)

GENERAL COMPARISON​

Property	Anastrozole (Arimidex)	Letrozole (Femara)	Exemestane (Aromasin)
Type	Non-steroidal, reversible	Non-steroidal, reversible	Steroidal, irreversible
Estrogen Suppression	~50–70% (dose dependent)	~80–98% (very potent)	~65–85% (irreversible)
Half-Life	~48 hrs	~40–60 hrs	~24–27 hrs
Rebound Risk	Medium if stopped fast	High (sharp increase)	Low (enzyme destroyed)
Titration Precision	High (easy microdose)	Moderate to difficult	Low (fixed dose tabs)
Bone Impact	Mild (long-term)	moderate to severe	moderate
Lipid impact	Mild, but could affect HDL	Moderate to severe	moderate
Onset of Suppression	~24 hours	Within hours	~24 hours (stronger than Anastrozole)
Peak Suppression	~2–4 days	~2–3 days	~2–3 days

PRICES​

Source	Anastrozole Price (1mg)	Letrozole Price (2.5mg)	Exemestane Price (25mg)
Pharma (Brand)	$5–$10	$8–$15	$10–$20
Generic (Indian)	$0.50–$1.50	$1–$3	$1–$4
UGL (Chinese)	$0.20–$0.50	$0.30–$1	$0.30–$1

SIDE EFFECTS​

Side Effect	Anastrozole (Arimidex)	Letrozole (Femera)	Exemestane (Aromasin)
Hot flashes	Common	Common	Common
Joint pain	Moderate	Moderate to severe	Mild to moderate
Fatigue	Mild to moderate	Moderate	Mild to moderate
Bone density loss	Mild (long-term use)	More severe if misused	Moderate (monitor needed)
Nausea	Mild	Mild to moderate	Mild
Mood changes	Possible	Possible	Possible
Headache	Occasionally	Occasionally	Occasionally
Increased cholesterol	Mild	Moderate to severe	Moderate
Muscle pain	Mild	Moderate	Mild

Exemestane is harsher on hair because of its androgenic metabolite, 17-β-hydroxyexemestane.
I’d recommend adding something like finasteride if you choose exemestane.
(That said, hair loss from exemestane only happens if you’re genetically prone to it)

Side effects like losing cognitive abilities only occur when your estrogen is under 10 pg/mL for a longer period of time
this and hair loss were the side effects I was afraid of the most, but as long as you know what youre doing, you don't have to worry about them

Here is a study that proves Ais are safe when it comes to influencing cognitive abilities
STUDY https://pubmed.ncbi.nlm.nih.gov/20421333

Also, Ais can increase levels of endogenous Testosterone production in men by 30-60% which is a lot

The biggest downside of non-steroidal Ai's is the possible estrogen rebound

Spoiler: estrogen rebound explained

Estrogen rebound is a phenomenon that occurs when the body experiences an increase in estrogen levels after discontinuing or reducing the dosage of aromatase inhibitors like Anastrozole or Letrozole.

This rebound effect happens because these AIs suppress the production of estrogen, but once the AI is stopped, estrogen levels rise temporarily as the body's natural production resumes.

This abrupt rise in the body’s natural production of estrogen could lead to premature closure of growth plates, potentially impacting final height.

Missing a few doses of a non-steroidal Aromatase Inhibitors could cause that, so be careful when using one
rebound can be strongly reduced by tapering off slowly instead of stopping suddenly

but in comparison to exemestane, letrozole and Anastrozole are cheaper and better studied

My personal choice is Exemestane, because it has the least side effects and estrogen rebound isn't a thing
(but like I said, every AI works, just keep E2 at 15-20 pg/mL
and if youre using a non-steroidal one, be careful that you dont forget to take them)

DOSAGE PROTOCOLS AND BLOODWORK
Test your E2 to find the dosage you probably need
1 week into your Ai you should do another blood test to see if you should adjust the dose
You want to Target blood estradiol levels of 15–20 pg/mL and never go under 10 pg/mL
(for reference, normal estradiol levels for teenagers are around 20-50 pg/mL)

If you can't do blood tests, youre basically playing russian roulette, so be careful
in that scenario start a low dose, for example 6,25mg of Exemestane and adjust the dose slowly on how you feel and symptoms you experience

symptoms of low estrogen
Sudden joint pain/dryness
Drop in libido or morning erections
Brain fog, mood drop, irritability
Dry skin or hair shedding increase
Unexplained fatigue
if these occure, lower the dose immediately

symptoms of high estrogen
Puffy face/water retention
Fat gain on hips/chest
Gynecomastia or nipple sensitivity
Emotional volatility or crying easily
Chronic bloating
if these occure you should up the dose

Also, here is an overview, how much different dosages suppress your estrogen

Spoiler: suppression of estrogen

Anastrozole:
0.5 mg → ~50–60% E2 suppression
1 mg → ~80–85% E2 suppression
5 mg → ~85–90% E2 suppression (plateau)
Letrozole:
0.25 mg → ~60–65% E2 suppression
0.5 mg → ~75–80% E2 suppression
1 mg → ~85–90% E2 suppression
2.5 mg → ~90–95% E2 suppression
Exemestane:
6.25 mg → ~30–35% E2 suppression
12.5 mg → ~55–60% E2 suppression
25 mg → ~85–95% E2 suppression

Avoid over suppression (estrogen crash) and Monitor symptoms and do bloodwork.

BlOODWORK
(budget friendly)

Spoiler: Bloodwork - what to test

Test Estradiol (E2)
Why: Directly shows if your estrogen is in your target range (~15–20 pg/ml).
When:
before the start to calculate the dose you need and then check again 1 week after the start
If everything is correct check 1 month later to see if its stable
then every 8-10 weeks
Total Testosterone + Free Testosterone
Why: AI can raise testosterone; high T can cause secondary effects (acne, aggression, libido swings).
When: Same time as E2 checks.

SHBG (Sex Hormone Binding Globulin)
Why: AI-induced changes in T and E2 affect SHBG, which changes free T availability.
When: every 8-12 weeks Alongside T/E2 checks.

Lipid Panel (Total Cholesterol, LDL, HDL, Triglycerides)
Why: Low E2 can lower HDL and raise LDL → cardiovascular risk.
When: Every 3 months.

Liver Enzymes (ALT, AST)
Why: Ais is metabolized in the liver; rare but possible liver stress.
When: Every 3 months or if symptoms appear.
(important if you drink alcohol)

Bone Health (long-term)
Why: Chronically low E2 can reduce bone density.
When: DEXA scan after 12+ months if running AI long-term.
(optional, but would be good)

simply put together

the baseline test would be:
E2 (sensitive), Total T, Free T, SHBG, Lipid Panel, ALT/AST

around 1 week after AI start:
E2 (sensitive) (optional Total T)

then E2 (sensitive), Total T, Free T, SHBG
every 8-10 weeks and lipids + liver enzymes every 3 months

You can do blood tests in private labs

IMPORTANT NOTES AND TIPS
The time when you take your Ai is not important (should still be around the same time)
But taking your Ai with a meal is
(alternatively, you can take your ai with a tablespoon of olive oil)

Storage:
Dry location with an ideal temperature of 15–25°C and no sun exposure
(just put it in your drawer)

Hormones return to baseline within 2–4 weeks after you stop taking your ai

weird, but don't eat Grapefruits and don't drink Grapefruit Juice
Grapefruit and its juice contain compounds that block the liver enzyme CYP3A4, which helps break down many drugs, including aromatase inhibitors.
This blockage can cause the ai to build up in your blood, and with that increase the risk of side effects

CLINICAL STUDIES OF HEIGHT INCREASE WITH AIS
View attachment 4005487
STUDY https://ijpeonline.biomedcentral.com/articles/10.1186/1687-9856-2015-4

Aromatase inhibitors Alone
Boys with idiopathic short stature or delayed puberty treated with anastrozole (AI) showed around 5 cm increase in predicted adult height by delaying growth plate closure
STUDY https://pubmed.ncbi.nlm.nih.gov/16189252

Growth Hormone (HGH) Alone:
This study looked at kids with idiopathic short stature (ISS), meaning normal GH levels but short height.
HGH treatment increased adult height by an average of 4–6 cm compared to untreated children.
STUDY https://umraniyepediatri.com/storage/upload/pdfs/1732279204-en.pdf

Combination Therapy (AI + HGH):
combining growth hormone with aromatase inhibitors in adolescent boys with idiopathic short stature led to an average adult height increase of about 6 to 9 cm.
STUDY https://academic.oup.com/jcem/article/110/9/e2871/8125692?login=false

HOPEFUL
Boys grow 2.13 cm in average after the age of 18 without anything
a study shows, that on average, boys grew an additional 2.13 cm between ages 18 and 27, with some increasing by as much as 7 cm
absolutely hopeful study
STUDY https://pubmed.ncbi.nlm.nih.gov/6638938

AIS IN CONTEXT OF BODYBUILDING
View attachment 4007910
i dont want this topic to be left out completely, but i will just cover the most important things

because of higher testosterone levels, the body converts more testosterone to estrogen
Ais can help to control estrogen levels during steroid cycles,
preventing side effects like water retention, bloating, and gynecomastia.

They’re used to maintain a healthy testosterone-to-estrogen balance, which supports better muscle gains, mood, and overall performance.
Additionally, by limiting estrogen, AIs can reduce fat storage and help bodybuilders achieve a leaner, more defined physique.

When Ais come to play in bodybuilding
if your Estradiol is too high and you experience side effects like
-Gyno
-Water retention
-Severe acne
-Mood swings (irritability or depression)

At High Doses or for Estrogen-Sensitive Users
some users don't need one even with +500 mg test a week
while some require an AI even with just 250 mg/week
(At ~500 mg testosterone a week most need an AI)

During Contest Prep
Ais reduce water retention, many bodybuilders use that to achieve a more defined and dryer look

Post-Cycle therapy (PCT)
After a steroid cycle to restore natural testosterone production
Often combined with SERMs (Clomid, Nolvadex)

SPECIAL TOPICS
AI Resistance
true resistance to aromatase inhibitors in men is very rare, but possible
In bodybuilding “resistance” usually means underdosing,
poor absorption of the product, or genetic differences in aromatase activity

In practice:
If estrogen stays high despite seemingly adequate AI dosing,
first rule out fake/underdosed product and high androgen load before assuming true resistance

Many UGL AIs are underdosed
Buy from tested sources (Janoshik reports).
and see how much impact they have on your E2 via bloodwork

Myths about estrogen
Myth 1: “Lower estrogen = more muscle gains.”
Truth: Too little estrogen impairs strength, recovery, joint health, and IGF-1 signaling, all critical for muscle growth.

Myth 2: “Estrogen is bad for men and should be eliminated completely.”
Truth: Estrogen plays important roles in men, including bone haelth, brain function, and regulating libido

Myth 3: “If you don’t feel symptoms, your estrogen is fine.”
Truth: Some people have no noticeable symptoms until E2 is way out of range, that's why blood tests are so important
(for example, my E2 was at 56 pg/mL and i didn't notice anything)

CONCLUSION

Spoiler: conclusion

Ais work by lowering estrogen, which delays the closing of your growth plates, giving you more time to grow taller and with that
are a great tool that could give you another 1-6cm, depending on your bone age

(keep in mind that if youre 5'7 at 16 or older with a similar bone age, nothing except LL will bring you to 6'0)

The younger your bone age, the more you can grow through all of this

even tough they are different, the type of Ai you use doesnt really matter
but understanding how they work does

So, while AIs can help extend your growth window, they’re not some magic pill, get your bloodwork done and dont be a retard

if i forget anything you want to know, just tell me

other threads i strongly recommend reading

Spoiler: threads

Another guide on HGH + Ai
https://looksmax.org/threads/theore...omatase-inhibitor-for-pubertymaxxing.1061735/

Heightmaxxing experience with HGH + Ai
https://looksmax.org/threads/coveri...xperience-results-tips-and-struggles.1172898/

About HGH
https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

hope we all ascend
-renos

Spoiler: tags

@Zagro @Mainlander @MyDreamIsToBe183CM

​

Dnrd looks high iq I can’t use this shit tho

 

[Deleted member 2461]

das hat so lange gedauert und ich habe nicht mal sticky bekommen

@Gengar @Gargantuan help my boy out and give him sticky for this high IQ thread

 

[Sadist]

inb4 botb

 

[renos]

inb4 botb

Hearing this from someone like you means a lot to me

have a great day

 

[Sadist]

Hearing this from someone like you means a lot to me

dont make me blush..

have a great day

likewise man

 

[yuuwaku]

I'm 185/6'1 at 18,5.

такая же история ток я 18.1

 

[renos]

@kazama

 

[kazama]

When it comes to heightmaxxing people always recommend the combination of HGH and an AI
but what even are Aromatase Inhibitors?

This guide will teach you everything you need to know about Aromatase inhibitors!
read this guide if you want to gain knowledge about HGH → https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

THE ROLE OF ESTROGEN WHEN IT COMES TO HEIGHT
Human linear growth occurs at the epiphyseal (growth) plates of long bones, which are zones of cartilage undergoing endochondral ossification.
These plates consist of:
Resting zone: reserves of chondrocytes
Proliferative zone: active cell division
Hypertrophic zone: cell enlargement and mineralization

View attachment 4004032
So, bone lengthening continues until the growth plate closes, which marks the end of height increase.
This closure process is triggered by estrogen
How?
Estrogen closes growth plates by binding to estrogen receptor alpha on chondrocytes, pushing them to mature faster while depleting the reserve of stem-like cells that keep the plate active once these cells mature too quickly, the growth plate runs out of new cells that can make more bone length.

Estrogen also makes the plate release signals that pull in blood vessels, which bring bone building cells
These cells replace the last bits of cartilage with solid bone.
When that happens, the growth plate turns into a thin bony line, and you can’t get any taller.

So make sure your plates are open before you take action
you can confirm this through an x-ray of your hand or knee

Spoiler: open vs closed growth plates

View attachment 4008423

The younger your bone age, the more potential you have to grow
ideally it should be younger than 16, but even after that you could grow a few more cm

but once plates are closed, Limb lenghtening is the only way to increase height other than fixing posture and wearing shoe-lifts

WHAT ARE AROMATASE INHIBITORS?

Spoiler: history

The story starts back in the 1950s and 60s when scientists first figured out how estrogen is made in the body.
They realized that if you could block the aromatase enzyme, you could lower estrogen levels and potentially slow down some type of cancers

In the 1970s, the first aromatase inhibitors were developed. These early drugs, like aminoglutethimide, weren’t very selective and had a lot of side effects.
They worked by binding tightly to the enzyme and basically breaking it, but because they weren’t very specific, patients often had issues.

Then, during the 1980s and early 90s, researchers worked on making better inhibitors.
Nonsteroidal ones came along, such as fadrozole and vorozole, which were safer and more targeted.

The big breakthrough happened in the 1990s: anastrozole, letrozole, and exemestane were invented
These drugs were more effective, had fewer side effects, and became the new standard treatment for hormone-sensitive breast cancer
They’re still widely used today because they work well and patients tolerate them better than older drugs.

Aromatase inhibitors also come to play for treating male hypogonadism or delaying puberty
(and with that being able to grow for a longer period of time)

Aromatase inhibitors are compounds that block or kill the enzyme aromatase, which converts testosterone into estrogen.

Spoiler: what is aromatase

Aromatase is a cytochrome P450 enzyme, encoded bythe CYP19A1 gene.
It catalyzes the aromatization of the A-ring ofandrogens, specifically:
Testosterone into Estradiol and Androstenedione intoEstrone

(Estrogen refers to a group of hormones that include estradiol, estrone, and estriol, with estradiol being the most potent and prevalent)

By lowering estrogen levels, AIs can delay epiphyseal fusion, extending the window for longitudinal bone growth

The Aromatization Reaction (Biochemistry)
At the molecular level, aromatase performs a three-stepoxidation of the androgen substrate’s A-ring:
Hydroxylation of the 19-methyl group (C19).
Conversion to a formyl group.
Aromatization of the A-ring, forming an aromaticphenol (the hallmark of estrogen).

This process is NADPH-dependent, and localiezd in the endoplasmic reticulum of cells
By taking an aromatase inhibitor we can block this process leading to less estrogen

ANASTROZOLE, LETROZOLE AND EXEMESTANE IN COMPARISON
The main difference is that anastrozole and letrozole are non-steroidal aromatase inhibitors, while exemestane is a steroidal aromatase inhibitor.
Simply put, this means that anastrozole and letrozole anesthetize the aromatase enzyme while exemestane kills the aromatase enzyme
(The enzyme is reproduced by the body)

GENERAL COMPARISON​

Property	Anastrozole (Arimidex)	Letrozole (Femara)	Exemestane (Aromasin)
Type	Non-steroidal, reversible	Non-steroidal, reversible	Steroidal, irreversible
Estrogen Suppression	~50–70% (dose dependent)	~80–98% (very potent)	~65–85% (irreversible)
Half-Life	~48 hrs	~40–60 hrs	~24–27 hrs
Rebound Risk	Medium if stopped fast	High (sharp increase)	Low (enzyme destroyed)
Titration Precision	High (easy microdose)	Moderate to difficult	Low (fixed dose tabs)
Bone Impact	Mild (long-term)	moderate to severe	moderate
Lipid impact	Mild, but could affect HDL	Moderate to severe	moderate
Onset of Suppression	~24 hours	Within hours	~24 hours (stronger than Anastrozole)
Peak Suppression	~2–4 days	~2–3 days	~2–3 days

PRICES​

Source	Anastrozole Price (1mg)	Letrozole Price (2.5mg)	Exemestane Price (25mg)
Pharma (Brand)	$5–$10	$8–$15	$10–$20
Generic (Indian)	$0.50–$1.50	$1–$3	$1–$4
UGL (Chinese)	$0.20–$0.50	$0.30–$1	$0.30–$1

SIDE EFFECTS​

Side Effect	Anastrozole (Arimidex)	Letrozole (Femera)	Exemestane (Aromasin)
Hot flashes	Common	Common	Common
Joint pain	Moderate	Moderate to severe	Mild to moderate
Fatigue	Mild to moderate	Moderate	Mild to moderate
Bone density loss	Mild (long-term use)	More severe if misused	Moderate (monitor needed)
Nausea	Mild	Mild to moderate	Mild
Mood changes	Possible	Possible	Possible
Headache	Occasionally	Occasionally	Occasionally
Increased cholesterol	Mild	Moderate to severe	Moderate
Muscle pain	Mild	Moderate	Mild

Exemestane is harsher on hair because of its androgenic metabolite, 17-β-hydroxyexemestane.
I’d recommend adding something like ru58841 if you choose exemestane.
(That said, hair loss from exemestane only happens if you’re genetically prone to it)

Side effects like losing cognitive abilities only occur when your estrogen is under 10 pg/mL for a longer period of time
this and hair loss were the side effects I was afraid of the most, but as long as you know what youre doing, you don't have to worry about them

Here is a study that proves Ais are safe when it comes to influencing cognitive abilities
STUDY https://pubmed.ncbi.nlm.nih.gov/20421333

Also, Ais can increase levels of endogenous Testosterone production in men by 30-60% which is a lot

The biggest downside of non-steroidal Ai's is the possible estrogen rebound

Spoiler: estrogen rebound explained

Estrogen rebound is a phenomenon that occurs when the body experiences an increase in estrogen levels after discontinuing or reducing the dosage of aromatase inhibitors like Anastrozole or Letrozole.

This rebound effect happens because these AIs suppress the production of estrogen, but once the AI is stopped, estrogen levels rise temporarily as the body's natural production resumes.

This abrupt rise in the body’s natural production of estrogen could lead to premature closure of growth plates, potentially impacting final height.

Missing a few doses of a non-steroidal Aromatase Inhibitors could cause that, so be careful when using one
rebound can be strongly reduced by tapering off slowly instead of stopping suddenly

but in comparison to exemestane, letrozole and Anastrozole are cheaper and better studied

My personal choice is Exemestane, because it has the least side effects and estrogen rebound isn't a thing
(but like I said, every AI works, just keep E2 at 15-20 pg/mL
and if youre using a non-steroidal one, be careful that you dont forget to take them)

DOSAGE PROTOCOLS AND BLOODWORK
Test your E2 to find the dosage you probably need
1 week into your Ai you should do another blood test to see if you should adjust the dose
You want to Target blood estradiol levels of 15–20 pg/mL and never go under 10 pg/mL
(for reference, normal estradiol levels for teenagers are around 20-50 pg/mL)

If you can't do blood tests, youre basically playing russian roulette, so be careful
in that scenario start a low dose, for example 6,25mg of Exemestane and adjust the dose slowly on how you feel and symptoms you experience

symptoms of low estrogen
Sudden joint pain/dryness
Drop in libido or morning erections
Brain fog, mood drop, irritability
Dry skin or hair shedding increase
Unexplained fatigue
if these occure, lower the dose immediately

symptoms of high estrogen
Puffy face/water retention
Fat gain on hips/chest
Gynecomastia or nipple sensitivity
Emotional volatility or crying easily
Chronic bloating
if these occure you should up the dose

Also, here is an overview, how much different dosages suppress your estrogen

Spoiler: suppression of estrogen

Anastrozole:
0.5 mg → ~50–60% E2 suppression
1 mg → ~80–85% E2 suppression
5 mg → ~85–90% E2 suppression (plateau)
Letrozole:
0.25 mg → ~60–65% E2 suppression
0.5 mg → ~75–80% E2 suppression
1 mg → ~85–90% E2 suppression
2.5 mg → ~90–95% E2 suppression
Exemestane:
6.25 mg → ~30–35% E2 suppression
12.5 mg → ~55–60% E2 suppression
25 mg → ~85–95% E2 suppression

Avoid over suppression (estrogen crash) and Monitor symptoms and do bloodwork.

BlOODWORK
(budget friendly)

Spoiler: Bloodwork - what to test

Test Estradiol (E2)
Why: Directly shows if your estrogen is in your target range (~15–20 pg/ml).
When:
before the start to calculate the dose you need and then check again 1 week after the start
If everything is correct check 1 month later to see if its stable
then every 8-10 weeks
Total Testosterone + Free Testosterone
Why: AI can raise testosterone; high T can cause secondary effects (acne, aggression, libido swings).
When: Same time as E2 checks.

SHBG (Sex Hormone Binding Globulin)
Why: AI-induced changes in T and E2 affect SHBG, which changes free T availability.
When: every 8-12 weeks Alongside T/E2 checks.

Lipid Panel (Total Cholesterol, LDL, HDL, Triglycerides)
Why: Low E2 can lower HDL and raise LDL → cardiovascular risk.
When: Every 3 months.

Liver Enzymes (ALT, AST)
Why: Ais is metabolized in the liver; rare but possible liver stress.
When: Every 3 months or if symptoms appear.
(important if you drink alcohol)

Bone Health (long-term)
Why: Chronically low E2 can reduce bone density.
When: DEXA scan after 12+ months if running AI long-term.
(optional, but would be good)

simply put together

the baseline test would be:
E2 (sensitive), Total T, Free T, SHBG, Lipid Panel, ALT/AST

around 1 week after AI start:
E2 (sensitive) (optional Total T)

then E2 (sensitive), Total T, Free T, SHBG
every 8-10 weeks and lipids + liver enzymes every 3 months

You can do blood tests in private labs

IMPORTANT NOTES AND TIPS
The time when you take your Ai is not important (should still be around the same time)
But taking your Ai with a meal is
(alternatively, you can take your ai with a tablespoon of olive oil)

Storage:
Dry location with an ideal temperature of 15–25°C and no sun exposure
(just put it in your drawer)

Hormones return to baseline within 2–4 weeks after you stop taking your ai

weird, but don't eat Grapefruits and don't drink Grapefruit Juice
Grapefruit and its juice contain compounds that block the liver enzyme CYP3A4, which helps break down many drugs, including aromatase inhibitors.
This blockage can cause the ai to build up in your blood, and with that increase the risk of side effects

CLINICAL STUDIES OF HEIGHT INCREASE WITH AIS
View attachment 4005487
STUDY https://ijpeonline.biomedcentral.com/articles/10.1186/1687-9856-2015-4

Aromatase inhibitors Alone
Boys with idiopathic short stature or delayed puberty treated with anastrozole (AI) showed around 5 cm increase in predicted adult height by delaying growth plate closure
STUDY https://pubmed.ncbi.nlm.nih.gov/16189252

Growth Hormone (HGH) Alone:
This study looked at kids with idiopathic short stature (ISS), meaning normal GH levels but short height.
HGH treatment increased adult height by an average of 4–6 cm compared to untreated children.
STUDY https://umraniyepediatri.com/storage/upload/pdfs/1732279204-en.pdf

Combination Therapy (AI + HGH):
combining growth hormone with aromatase inhibitors in adolescent boys with idiopathic short stature led to an average adult height increase of about 6 to 9 cm.
STUDY https://academic.oup.com/jcem/article/110/9/e2871/8125692?login=false

HOPEFUL
Boys grow 2.13 cm in average after the age of 18 without anything
a study shows, that on average, boys grew an additional 2.13 cm between ages 18 and 27, with some increasing by as much as 7 cm
absolutely hopeful study
STUDY https://pubmed.ncbi.nlm.nih.gov/6638938

AIS IN CONTEXT OF BODYBUILDING
View attachment 4007910
i dont want this topic to be left out completely, but i will just cover the most important things

because of higher testosterone levels, the body converts more testosterone to estrogen
Ais can help to control estrogen levels during steroid cycles,
preventing side effects like water retention, bloating, and gynecomastia.

They’re used to maintain a healthy testosterone-to-estrogen balance, which supports better muscle gains, mood, and overall performance.
Additionally, by limiting estrogen, AIs can reduce fat storage and help bodybuilders achieve a leaner, more defined physique.

When Ais come to play in bodybuilding
if your Estradiol is too high and you experience side effects like
-Gyno
-Water retention
-Severe acne
-Mood swings (irritability or depression)

At High Doses or for Estrogen-Sensitive Users
some users don't need one even with +500 mg test a week
while some require an AI even with just 250 mg/week
(At ~500 mg testosterone a week most need an AI)

During Contest Prep
Ais reduce water retention, many bodybuilders use that to achieve a more defined and dryer look

Post-Cycle therapy (PCT)
After a steroid cycle to restore natural testosterone production
Often combined with SERMs (Clomid, Nolvadex)

SPECIAL TOPICS
AI Resistance
true resistance to aromatase inhibitors in men is very rare, but possible
In bodybuilding “resistance” usually means underdosing,
poor absorption of the product, or genetic differences in aromatase activity

In practice:
If estrogen stays high despite seemingly adequate AI dosing,
first rule out fake/underdosed product and high androgen load before assuming true resistance

Many UGL AIs are underdosed
Buy from tested sources (Janoshik reports).
and see how much impact they have on your E2 via bloodwork

Myths about estrogen
Myth 1: “Lower estrogen = more muscle gains.”
Truth: Too little estrogen impairs strength, recovery, joint health, and IGF-1 signaling, all critical for muscle growth.

Myth 2: “Estrogen is bad for men and should be eliminated completely.”
Truth: Estrogen plays important roles in men, including bone haelth, brain function, and regulating libido

Myth 3: “If you don’t feel symptoms, your estrogen is fine.”
Truth: Some people have no noticeable symptoms until E2 is way out of range, that's why blood tests are so important
(for example, my E2 was at 56 pg/mL and i didn't notice anything)

CONCLUSION

Spoiler: conclusion

Ais work by lowering estrogen, which delays the closing of your growth plates, giving you more time to grow taller and with that
are a great tool that could give you another 1-6cm, depending on your bone age

(keep in mind that if youre 5'7 at 16 or older with a similar bone age, nothing except LL will bring you to 6'0)

The younger your bone age, the more you can grow through all of this

even tough they are different, the type of Ai you use doesnt really matter
but understanding how they work does

So, while AIs can help extend your growth window, they’re not some magic pill, get your bloodwork done and dont be a retard

if i forget anything you want to know, just tell me

other threads i strongly recommend reading

Spoiler: threads

Another guide on HGH + Ai
https://looksmax.org/threads/theore...omatase-inhibitor-for-pubertymaxxing.1061735/

Heightmaxxing experience with HGH + Ai
https://looksmax.org/threads/coveri...xperience-results-tips-and-struggles.1172898/

About HGH
https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

hope we all ascend
-renos

Spoiler: tags

@Zagro @Mainlander @MyDreamIsToBe183CM

​

Bookmarked, I need to read this like a bible tbh. Amazing formatting, I just love this
Tag me in any thread ur bro

 

[renos]

Bookmarked, I need to read this like a bible tbh. Amazing formatting, I just love this

thank you man

Tag me in any thread ur bro

i will

 

[lokit]

thank you man

i will

should i start aromasin 6mg eod or 12mg eod? i cant get bloodwork done unfortunately,,, i alrdy have the shi home lowk

 

[renos]

should i start aromasin 6mg eod or 12mg eod? i cant get bloodwork done unfortunately,,, i alrdy have the shi home lowk

Start at 6,25mg and slowly adjust the dose on how you feel

 

[lokit]

Start at 6,25mg and slowly adjust the dose on how you feel

How long should I take it before evaluating how I feel? Been taking it for almost a week now, also started hgh

 

[Brian Weber]

Boys grow 2.13 cm in average after the age of 18 without anything

did u get this from me bhai

 

[renos]

did u get this from me bhai

No from @MyDreamIsToBe183CM if I remember correctly

 

[renos]

How long should I take it before evaluating how I feel?

1-2 weeks would be enough

 

[6ft8pslslayer]

12.5mg of exemestane once every 2 days is what imma do

 

[Brian Weber]

isnt 15-20pg estrogen cope in studies they put it down to 5pg. 20-30 is the natural range so ur really not lowering it that much

 

[renos]

isnt 15-20pg estrogen cope in studies they put it down to 5pg. 20-30 is the natural range so ur really not lowering it that much

Studies sometimes drove estradiol down toward 5pg/mL, but that was done under medical supervision for specific indications and usually just for a short period of time.

Running E2 that low for months would be retarded, because it would most likely just cause things like bone/hair loss, joint pain, depression and also negatively influence your brain function.

The 15–20 pg/mL recommendation is a compromise.
Having E2 Levels of 10-15pg/mL probably also wouldn’t cause any real issues.
I just say you shouldn’t go under 10pg/mL because there the cons outweigh the pros.

 

[Brian Weber]

Studies sometimes drove estradiol down toward 5pg/mL, but that was done under medical supervision for specific indications and usually just for a short period of time.

Running E2 that low for months would be retarded, because it would most likely just cause things like bone/hair loss, joint pain, depression and also negatively influence your brain function.

The 15–20 pg/mL recommendation is a compromise.
Having E2 Levels of 10-15pg/mL probably also wouldn’t cause any real issues.
I just say you shouldn’t go under 10pg/mL because there the cons outweigh the pros.

true but having estrogen at 15-20 would only slow fusure mildly its not like ur putting a fat break on ur bone age

 

[renos]

true but having estrogen at 15-20 would only slow fusure mildly its not like ur putting a fat break on ur bone age

HGH naturally pushes your estrogen a bit higher, so it’s important to remember how harsh sudden spikes can be on your growth plates

Keeping your levels steady in the 15–20 pg/mL range (down to 10pg/mL is also okay, like I already mentioned) makes those spikes far less damaging, then they would usually be for your growth plates

 

[notcasper]

When it comes to heightmaxxing people always recommend the combination of HGH and an AI
but what even are Aromatase Inhibitors?


Also, here is an overview, how much different dosages suppress your estrogen

Spoiler: suppression of estrogen

Anastrozole:
0.5 mg → ~50–60% E2 suppression
1 mg → ~80–85% E2 suppression
5 mg → ~85–90% E2 suppression (plateau)
Letrozole:
0.25 mg → ~60–65% E2 suppression
0.5 mg → ~75–80% E2 suppression
1 mg → ~85–90% E2 suppression
2.5 mg → ~90–95% E2 suppression
Exemestane:
6.25 mg → ~30–35% E2 suppression
12.5 mg → ~55–60% E2 suppression
25 mg → ~85–95% E2 suppression

Avoid over suppression (estrogen crash) and Monitor symptoms and do bloodwork.

BlOODWORK
(budget friendly)

Spoiler: Bloodwork - what to test

Test Estradiol (E2)
Why: Directly shows if your estrogen is in your target range (~15–20 pg/ml).
When:

i was on 6.25mg exemestane EOD and it brought my levels to 14-32ng/dl so i upped to 12.5 mg EOD hopefully my levels will be in good range

 

[Dizzle]

Myth 3: “If you don’t feel symptoms, your estrogen is fine.”
Truth: Some people have no noticeable symptoms until E2 is way out of range, that's why blood tests are so important
(for example, my E2 was at 56 pg/mL and i didn't notice anything)
83]@MyDreamIsToBe183CM[/USER] [/SPOILER]


​

25m aromasin didnt give me side effects so i just tried 50 once but it didnt grant any noticable difference/side effects. Should i be worried? was even contemplating actually doing bloods.

 

[renos]

25m aromasin didnt give me side effects so i just tried 50 once but it didnt grant any noticable difference/side effects. Should i be worried? was even contemplating actually doing bloods.

You probably got scammed

 

[Dizzle]

You probably got scammed

Ssa pretty authentic no?

 

[renos]

Ssa pretty authentic no?

weird, i also bought my ai from ssa so it should be legit
do bloods

 

[Dizzle]

weird, i also bought my ai from ssa so it should be legit
do bloods

can we pm?

 

[Deleted member 153567]

Ssa pretty authentic no?

their cialis is definitly real, got acid reflux when i went for the biggest pump in the gym

the other stuff is pretty legit too, maybe i should test their ghk-cu at the FTIR at school

 

[fishinthesee]

their cialis is definitly real, got acid reflux when i went for the biggest pump in the gym

the other stuff is pretty legit too, maybe i should test their ghk-cu at the FTIR at school

using school FTIR to test your research chemicals

the ND stare u give them when they ask why you want to test them

 

[Deleted member 153567]

using school FTIR to test your research chemicals

the ND stare u give them when they ask why you want to test them

using the school hplc/ms/ms to test my own bloods

 

[fishinthesee]

using the school hplc/ms/ms to test my own bloods

based tbh

 

[Deleted member 190626]

12.5mg of exemestane once every 2 days is what imma do

hair loss final boss

 

[6ft8pslslayer]

hair loss final boss

haha my hair genetics are very good idgaf, im never going bald

 

[Deleted member 190626]

haha my hair genetics are very good idgaf, im never going bald

It causes hair loss

 

[Musa_ethnic]

Когда речь идет о максимальном росте, люди всегда рекомендуют комбинацию ГР и ИА.
но что такое ингибиторы ароматазы?

Это руководство научит вас всему, что вам нужно знать об ингибиторах ароматазы!
прочитайте это руководство, если вы хотите получить знания о гормоне роста → https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

РОЛЬ ЭСТРОГЕНА , КОГДА ОНО ДОСТИГАЕТ ВЫСОТЫ
Линейный рост человека происходит за счет эпифизарных (ростовых) пластинок длинных трубчатых костей, представляющих собой зоны хряща, подвергающиеся эндохондральному окостенению .
Эти пластины состоят из:
Зона покоя : резервы хондроцитов
Пролиферативная зона : активное деление клеток
Гипертрофическая зона : увеличение клеток и минерализация

View attachment 4004032
Таким образом, удлинение костей продолжается до тех пор, пока не закроется пластинка роста, что знаменует собой окончание увеличения роста.
Этот процесс закрытия запускается эстрогеном.
Как?
Estrogen closes growth plates by binding to estrogen receptor alpha on chondrocytes, pushing them to mature faster while depleting the reserve of stem-like cells that keep the plate active once these cells mature too quickly, the growth plate runs out of new cells that can make more bone length.

Estrogen also makes the plate release signals that pull in blood vessels, which bring bone building cells
These cells replace the last bits of cartilage with solid bone.
When that happens, the growth plate turns into a thin bony line, and you can’t get any taller.

So make sure your plates are open before you take action
you can confirm this through an x-ray of your hand or knee

Spoiler: open vs closed growth plates

View attachment 4008423

The younger your bone age, the more potential you have to grow
ideally it should be younger than 16, but even after that you could grow a few more cm

but once plates are closed, Limb lenghtening is the only way to increase height other than fixing posture and wearing shoe-lifts

WHAT ARE AROMATASE INHIBITORS?

Spoiler: history

The story starts back in the 1950s and 60s when scientists first figured out how estrogen is made in the body.
They realized that if you could block the aromatase enzyme, you could lower estrogen levels and potentially slow down some type of cancers

In the 1970s, the first aromatase inhibitors were developed. These early drugs, like aminoglutethimide, weren’t very selective and had a lot of side effects.
They worked by binding tightly to the enzyme and basically breaking it, but because they weren’t very specific, patients often had issues.

Then, during the 1980s and early 90s, researchers worked on making better inhibitors.
Nonsteroidal ones came along, such as fadrozole and vorozole, which were safer and more targeted.

The big breakthrough happened in the 1990s: anastrozole, letrozole, and exemestane were invented
These drugs were more effective, had fewer side effects, and became the new standard treatment for hormone-sensitive breast cancer
They’re still widely used today because they work well and patients tolerate them better than older drugs.

Aromatase inhibitors also come to play for treating male hypogonadism or delaying puberty
(and with that being able to grow for a longer period of time)

Aromatase inhibitors are compounds that block or kill the enzyme aromatase, which converts testosterone into estrogen.

Spoiler: what is aromatase

Aromatase is a cytochrome P450 enzyme, encoded bythe CYP19A1 gene.
It catalyzes the aromatization of the A-ring ofandrogens, specifically:
Testosterone into Estradiol and Androstenedione intoEstrone

(Estrogen refers to a group of hormones that include estradiol, estrone, and estriol, with estradiol being the most potent and prevalent)

By lowering estrogen levels, AIs can delay epiphyseal fusion, extending the window for longitudinal bone growth

The Aromatization Reaction (Biochemistry)
At the molecular level, aromatase performs a three-stepoxidation of the androgen substrate’s A-ring:
Hydroxylation of the 19-methyl group (C19).
Conversion to a formyl group.
Aromatization of the A-ring, forming an aromaticphenol (the hallmark of estrogen).

This process is NADPH-dependent, and localiezd in the endoplasmic reticulum of cells
By taking an aromatase inhibitor we can block this process leading to less estrogen

ANASTROZOLE, LETROZOLE AND EXEMESTANE IN COMPARISON
The main difference is that anastrozole and letrozole are non-steroidal aromatase inhibitors, while exemestane is a steroidal aromatase inhibitor.
Simply put, this means that anastrozole and letrozole anesthetize the aromatase enzyme while exemestane kills the aromatase enzyme
(The enzyme is reproduced by the body)

GENERAL COMPARISON​

Property	Anastrozole (Arimidex)	Letrozole (Femara)	Exemestane (Aromasin)
Type	Non-steroidal, reversible	Non-steroidal, reversible	Steroidal, irreversible
Estrogen Suppression	~50–70% (dose dependent)	~80–98% (very potent)	~65–85% (irreversible)
Half-Life	~48 hrs	~40–60 hrs	~24–27 hrs
Rebound Risk	Medium if stopped fast	High (sharp increase)	Low (enzyme destroyed)
Titration Precision	High (easy microdose)	Moderate to difficult	Low (fixed dose tabs)
Bone Impact	Mild (long-term)	moderate to severe	moderate
Lipid impact	Mild, but could affect HDL	Moderate to severe	moderate
Onset of Suppression	~24 hours	Within hours	~24 hours (stronger than Anastrozole)
Peak Suppression	~2–4 days	~2–3 days	~2–3 days

PRICES​

Source	Anastrozole Price (1mg)	Letrozole Price (2.5mg)	Exemestane Price (25mg)
Pharma (Brand)	$5–$10	$8–$15	$10–$20
Generic (Indian)	$0.50–$1.50	$1–$3	$1–$4
UGL (Chinese)	$0.20–$0.50	$0.30–$1	$0.30–$1

SIDE EFFECTS​

Side Effect	Anastrozole (Arimidex)	Letrozole (Femera)	Exemestane (Aromasin)
Hot flashes	Common	Common	Common
Joint pain	Moderate	Moderate to severe	Mild to moderate
Fatigue	Mild to moderate	Moderate	Mild to moderate
Bone density loss	Mild (long-term use)	More severe if misused	Moderate (monitor needed)
Nausea	Mild	Mild to moderate	Mild
Mood changes	Possible	Possible	Possible
Headache	Occasionally	Occasionally	Occasionally
Increased cholesterol	Mild	Moderate to severe	Moderate
Muscle pain	Mild	Moderate	Mild

Exemestane is harsher on hair because of its androgenic metabolite, 17-β-hydroxyexemestane.
I’d recommend adding something like ru58841 if you choose exemestane.
(That said, hair loss from exemestane only happens if you’re genetically prone to it)

Side effects like losing cognitive abilities only occur when your estrogen is under 10 pg/mL for a longer period of time
this and hair loss were the side effects I was afraid of the most, but as long as you know what youre doing, you don't have to worry about them

Here is a study that proves Ais are safe when it comes to influencing cognitive abilities
STUDY https://pubmed.ncbi.nlm.nih.gov/20421333

Also, Ais can increase levels of endogenous Testosterone production in men by 30-60% which is a lot

The biggest downside of non-steroidal Ai's is the possible estrogen rebound

Spoiler: estrogen rebound explained

Estrogen rebound is a phenomenon that occurs when the body experiences an increase in estrogen levels after discontinuing or reducing the dosage of aromatase inhibitors like Anastrozole or Letrozole.

This rebound effect happens because these AIs suppress the production of estrogen, but once the AI is stopped, estrogen levels rise temporarily as the body's natural production resumes.

This abrupt rise in the body’s natural production of estrogen could lead to premature closure of growth plates, potentially impacting final height.

Missing a few doses of a non-steroidal Aromatase Inhibitors could cause that, so be careful when using one
rebound can be strongly reduced by tapering off slowly instead of stopping suddenly

but in comparison to exemestane, letrozole and Anastrozole are cheaper and better studied

My personal choice is Exemestane, because it has the least side effects and estrogen rebound isn't a thing
(but like I said, every AI works, just keep E2 at 15-20 pg/mL
and if youre using a non-steroidal one, be careful that you dont forget to take them)

DOSAGE PROTOCOLS AND BLOODWORK
Test your E2 to find the dosage you probably need
1 week into your Ai you should do another blood test to see if you should adjust the dose
You want to Target blood estradiol levels of 15–20 pg/mL and never go under 10 pg/mL
(for reference, normal estradiol levels for teenagers are around 20-50 pg/mL)

If you can't do blood tests, youre basically playing russian roulette, so be careful
in that scenario start a low dose, for example 6,25mg of Exemestane and adjust the dose slowly on how you feel and symptoms you experience

symptoms of low estrogen
Sudden joint pain/dryness
Drop in libido or morning erections
Brain fog, mood drop, irritability
Dry skin or hair shedding increase
Unexplained fatigue
if these occure, lower the dose immediately

symptoms of high estrogen
Puffy face/water retention
Fat gain on hips/chest
Gynecomastia or nipple sensitivity
Emotional volatility or crying easily
Chronic bloating
if these occure you should up the dose

Also, here is an overview, how much different dosages suppress your estrogen

Spoiler: suppression of estrogen

Anastrozole:
0.5 mg → ~50–60% E2 suppression
1 mg → ~80–85% E2 suppression
5 mg → ~85–90% E2 suppression (plateau)
Letrozole:
0.25 mg → ~60–65% E2 suppression
0.5 mg → ~75–80% E2 suppression
1 mg → ~85–90% E2 suppression
2.5 mg → ~90–95% E2 suppression
Exemestane:
6.25 mg → ~30–35% E2 suppression
12.5 mg → ~55–60% E2 suppression
25 mg → ~85–95% E2 suppression

Avoid over suppression (estrogen crash) and Monitor symptoms and do bloodwork.

BlOODWORK
(budget friendly)

Spoiler: Bloodwork - what to test

Test Estradiol (E2)
Why: Directly shows if your estrogen is in your target range (~15–20 pg/ml).
When:
before the start to calculate the dose you need and then check again 1 week after the start
If everything is correct check 1 month later to see if its stable
then every 8-10 weeks
Total Testosterone + Free Testosterone
Why: AI can raise testosterone; high T can cause secondary effects (acne, aggression, libido swings).
When: Same time as E2 checks.

SHBG (Sex Hormone Binding Globulin)
Why: AI-induced changes in T and E2 affect SHBG, which changes free T availability.
When: every 8-12 weeks Alongside T/E2 checks.

Lipid Panel (Total Cholesterol, LDL, HDL, Triglycerides)
Why: Low E2 can lower HDL and raise LDL → cardiovascular risk.
When: Every 3 months.

Liver Enzymes (ALT, AST)
Why: Ais is metabolized in the liver; rare but possible liver stress.
When: Every 3 months or if symptoms appear.
(important if you drink alcohol)

Bone Health (long-term)
Why: Chronically low E2 can reduce bone density.
When: DEXA scan after 12+ months if running AI long-term.
(optional, but would be good)

simply put together

the baseline test would be:
E2 (sensitive), Total T, Free T, SHBG, Lipid Panel, ALT/AST

around 1 week after AI start:
E2 (sensitive) (optional Total T)

then E2 (sensitive), Total T, Free T, SHBG
every 8-10 weeks and lipids + liver enzymes every 3 months

You can do blood tests in private labs

IMPORTANT NOTES AND TIPS
The time when you take your Ai is not important (should still be around the same time)
But taking your Ai with a meal is
(alternatively, you can take your ai with a tablespoon of olive oil)

Storage:
Dry location with an ideal temperature of 15–25°C and no sun exposure
(just put it in your drawer)

Hormones return to baseline within 2–4 weeks after you stop taking your ai

weird, but don't eat Grapefruits and don't drink Grapefruit Juice
Grapefruit and its juice contain compounds that block the liver enzyme CYP3A4, which helps break down many drugs, including aromatase inhibitors.
This blockage can cause the ai to build up in your blood, and with that increase the risk of side effects

CLINICAL STUDIES OF HEIGHT INCREASE WITH AIS
View attachment 4005487
STUDY https://ijpeonline.biomedcentral.com/articles/10.1186/1687-9856-2015-4

Aromatase inhibitors Alone
Boys with idiopathic short stature or delayed puberty treated with anastrozole (AI) showed around 5 cm increase in predicted adult height by delaying growth plate closure
STUDY https://pubmed.ncbi.nlm.nih.gov/16189252

Growth Hormone (HGH) Alone:
This study looked at kids with idiopathic short stature (ISS), meaning normal GH levels but short height.
HGH treatment increased adult height by an average of 4–6 cm compared to untreated children.
STUDY https://umraniyepediatri.com/storage/upload/pdfs/1732279204-en.pdf

Combination Therapy (AI + HGH):
combining growth hormone with aromatase inhibitors in adolescent boys with idiopathic short stature led to an average adult height increase of about 6 to 9 cm.
STUDY https://academic.oup.com/jcem/article/110/9/e2871/8125692?login=false

HOPEFUL
Boys grow 2.13 cm in average after the age of 18 without anything
a study shows, that on average, boys grew an additional 2.13 cm between ages 18 and 27, with some increasing by as much as 7 cm
absolutely hopeful study
STUDY https://pubmed.ncbi.nlm.nih.gov/6638938

AIS IN CONTEXT OF BODYBUILDING
View attachment 4007910
i dont want this topic to be left out completely, but i will just cover the most important things

because of higher testosterone levels, the body converts more testosterone to estrogen
Ais can help to control estrogen levels during steroid cycles,
preventing side effects like water retention, bloating, and gynecomastia.

They’re used to maintain a healthy testosterone-to-estrogen balance, which supports better muscle gains, mood, and overall performance.
Additionally, by limiting estrogen, AIs can reduce fat storage and help bodybuilders achieve a leaner, more defined physique.

When Ais come to play in bodybuilding
if your Estradiol is too high and you experience side effects like
-Gyno
-Water retention
-Severe acne
-Mood swings (irritability or depression)

At High Doses or for Estrogen-Sensitive Users
some users don't need one even with +500 mg test a week
while some require an AI even with just 250 mg/week
(At ~500 mg testosterone a week most need an AI)

During Contest Prep
Ais reduce water retention, many bodybuilders use that to achieve a more defined and dryer look

Post-Cycle therapy (PCT)
After a steroid cycle to restore natural testosterone production
Often combined with SERMs (Clomid, Nolvadex)

SPECIAL TOPICS
AI Resistance
true resistance to aromatase inhibitors in men is very rare, but possible
In bodybuilding “resistance” usually means underdosing,
poor absorption of the product, or genetic differences in aromatase activity

In practice:
If estrogen stays high despite seemingly adequate AI dosing,
first rule out fake/underdosed product and high androgen load before assuming true resistance

Many UGL AIs are underdosed
Buy from tested sources (Janoshik reports).
and see how much impact they have on your E2 via bloodwork

Myths about estrogen
Myth 1: “Lower estrogen = more muscle gains.”
Truth: Too little estrogen impairs strength, recovery, joint health, and IGF-1 signaling, all critical for muscle growth.

Миф 2: « Эстроген вреден для мужчин и должен быть полностью исключен из его приема » .
Правда: Эстроген играет важную роль в организме мужчин, включая здоровье костей, работу мозга и регуляцию либидо.

Миф 3: «Если вы не чувствуете симптомов, ваш эстроген в порядке».
Правда: У некоторых людей заметные симптомы отсутствуют, пока уровень E2 не выйдет за пределы нормы, поэтому анализы крови так важны.
(например, мой E2 был на уровне 56 пг/мл, и я ничего не заметил)

ЗАКЛЮЧЕНИЕ
[СПОЙЛЕР="заключение"]
АИС работает за счет снижения уровня эстрогена, который задерживает закрытие зон роста, давая вам больше времени, чтобы стать выше и с этим
отличный инструмент, который может дать вам еще 1–6 см, в зависимости от вашего костного возраста

(имейте в виду, что если в 16 лет ваш рост 5 футов 7 дюймов или больше и у вас схожий возраст костей, то ничто, кроме LL, не поможет вам достичь 6 футов 0 дюймов)

Чем моложе ваш костный возраст, тем больше вы сможете расти, проходя через все это.

даже если они разные, тип используемого вами ИИ не имеет значения
но понимание того, как они работают,

Итак, хотя ИИ могут помочь вам расширить окно роста, они не являются волшебной таблеткой. Сдайте анализ крови и не будьте идиотом.

Если я забуду что-нибудь, что вы хотите знать, просто скажите мне.:Удобно:

другие темы, которые я настоятельно рекомендую прочитать

Spoiler: темы

Еще одно руководство по ГР + ИИ
https://looksmax.org/threads/theoretical-in-detail-guide-on-how-to-safely-use-r-hgh-and-aromatase-inhibitor-for-pubertymaxxing.1061735/

Опыт максимального роста с помощью HGH + Ai
https://looksmax.org/threads/coveri...xperience-results-tips-and-struggles.1172898/

О гормоне роста
https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/
[/СПОЙЛЕР]
[/СПОЙЛЕР]

Spoiler: темы

[СПОЙЛЕР="заключение"]
[/СПОЙЛЕР]

надеюсь, мы все поднимемся
-ренос

Spoiler: теги

@Zagro @Mainlander @MyDreamIsToBe183CM [/

Spoiler: теги

[/spoiler

When it comes to heightmaxxing people always recommend the combination of HGH and an AI
but what even are Aromatase Inhibitors?

This guide will teach you everything you need to know about Aromatase inhibitors!
read this guide if you want to gain knowledge about HGH → https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

THE ROLE OF ESTROGEN WHEN IT COMES TO HEIGHT
Human linear growth occurs at the epiphyseal (growth) plates of long bones, which are zones of cartilage undergoing endochondral ossification.
These plates consist of:
Resting zone: reserves of chondrocytes
Proliferative zone: active cell division
Hypertrophic zone: cell enlargement and mineralization

View attachment 4004032
So, bone lengthening continues until the growth plate closes, which marks the end of height increase.
This closure process is triggered by estrogen
How?
Estrogen closes growth plates by binding to estrogen receptor alpha on chondrocytes, pushing them to mature faster while depleting the reserve of stem-like cells that keep the plate active once these cells mature too quickly, the growth plate runs out of new cells that can make more bone length.

Estrogen also makes the plate release signals that pull in blood vessels, which bring bone building cells
These cells replace the last bits of cartilage with solid bone.
When that happens, the growth plate turns into a thin bony line, and you can’t get any taller.

So make sure your plates are open before you take action
you can confirm this through an x-ray of your hand or knee

Spoiler: open vs closed growth plates

View attachment 4008423

The younger your bone age, the more potential you have to grow
ideally it should be younger than 16, but even after that you could grow a few more cm

but once plates are closed, Limb lenghtening is the only way to increase height other than fixing posture and wearing shoe-lifts

WHAT ARE AROMATASE INHIBITORS?

Spoiler: history

The story starts back in the 1950s and 60s when scientists first figured out how estrogen is made in the body.
They realized that if you could block the aromatase enzyme, you could lower estrogen levels and potentially slow down some type of cancers

In the 1970s, the first aromatase inhibitors were developed. These early drugs, like aminoglutethimide, weren’t very selective and had a lot of side effects.
They worked by binding tightly to the enzyme and basically breaking it, but because they weren’t very specific, patients often had issues.

Then, during the 1980s and early 90s, researchers worked on making better inhibitors.
Nonsteroidal ones came along, such as fadrozole and vorozole, which were safer and more targeted.

The big breakthrough happened in the 1990s: anastrozole, letrozole, and exemestane were invented
These drugs were more effective, had fewer side effects, and became the new standard treatment for hormone-sensitive breast cancer
They’re still widely used today because they work well and patients tolerate them better than older drugs.

Aromatase inhibitors also come to play for treating male hypogonadism or delaying puberty
(and with that being able to grow for a longer period of time)

Aromatase inhibitors are compounds that block or kill the enzyme aromatase, which converts testosterone into estrogen.

Spoiler: what is aromatase

Aromatase is a cytochrome P450 enzyme, encoded bythe CYP19A1 gene.
It catalyzes the aromatization of the A-ring ofandrogens, specifically:
Testosterone into Estradiol and Androstenedione intoEstrone

(Estrogen refers to a group of hormones that include estradiol, estrone, and estriol, with estradiol being the most potent and prevalent)

By lowering estrogen levels, AIs can delay epiphyseal fusion, extending the window for longitudinal bone growth

The Aromatization Reaction (Biochemistry)
At the molecular level, aromatase performs a three-stepoxidation of the androgen substrate’s A-ring:
Hydroxylation of the 19-methyl group (C19).
Conversion to a formyl group.
Aromatization of the A-ring, forming an aromaticphenol (the hallmark of estrogen).

This process is NADPH-dependent, and localiezd in the endoplasmic reticulum of cells
By taking an aromatase inhibitor we can block this process leading to less estrogen

ANASTROZOLE, LETROZOLE AND EXEMESTANE IN COMPARISON
The main difference is that anastrozole and letrozole are non-steroidal aromatase inhibitors, while exemestane is a steroidal aromatase inhibitor.
Simply put, this means that anastrozole and letrozole anesthetize the aromatase enzyme while exemestane kills the aromatase enzyme
(The enzyme is reproduced by the body)

GENERAL COMPARISON​

Property	Anastrozole (Arimidex)	Letrozole (Femara)	Exemestane (Aromasin)
Type	Non-steroidal, reversible	Non-steroidal, reversible	Steroidal, irreversible
Estrogen Suppression	~50–70% (dose dependent)	~80–98% (very potent)	~65–85% (irreversible)
Half-Life	~48 hrs	~40–60 hrs	~24–27 hrs
Rebound Risk	Medium if stopped fast	High (sharp increase)	Low (enzyme destroyed)
Titration Precision	High (easy microdose)	Moderate to difficult	Low (fixed dose tabs)
Bone Impact	Mild (long-term)	moderate to severe	moderate
Lipid impact	Mild, but could affect HDL	Moderate to severe	moderate
Onset of Suppression	~24 hours	Within hours	~24 hours (stronger than Anastrozole)
Peak Suppression	~2–4 days	~2–3 days	~2–3 days

PRICES​

Source	Anastrozole Price (1mg)	Letrozole Price (2.5mg)	Exemestane Price (25mg)
Pharma (Brand)	$5–$10	$8–$15	$10–$20
Generic (Indian)	$0.50–$1.50	$1–$3	$1–$4
UGL (Chinese)	$0.20–$0.50	$0.30–$1	$0.30–$1

SIDE EFFECTS​

Side Effect	Anastrozole (Arimidex)	Letrozole (Femera)	Exemestane (Aromasin)
Hot flashes	Common	Common	Common
Joint pain	Moderate	Moderate to severe	Mild to moderate
Fatigue	Mild to moderate	Moderate	Mild to moderate
Bone density loss	Mild (long-term use)	More severe if misused	Moderate (monitor needed)
Nausea	Mild	Mild to moderate	Mild
Mood changes	Possible	Possible	Possible
Headache	Occasionally	Occasionally	Occasionally
Increased cholesterol	Mild	Moderate to severe	Moderate
Muscle pain	Mild	Moderate	Mild

Exemestane is harsher on hair because of its androgenic metabolite, 17-β-hydroxyexemestane.
I’d recommend adding something like ru58841 if you choose exemestane.
(That said, hair loss from exemestane only happens if you’re genetically prone to it)

Side effects like losing cognitive abilities only occur when your estrogen is under 10 pg/mL for a longer period of time
this and hair loss were the side effects I was afraid of the most, but as long as you know what youre doing, you don't have to worry about them

Here is a study that proves Ais are safe when it comes to influencing cognitive abilities
STUDY https://pubmed.ncbi.nlm.nih.gov/20421333

Also, Ais can increase levels of endogenous Testosterone production in men by 30-60% which is a lot

The biggest downside of non-steroidal Ai's is the possible estrogen rebound

Spoiler: estrogen rebound explained

Estrogen rebound is a phenomenon that occurs when the body experiences an increase in estrogen levels after discontinuing or reducing the dosage of aromatase inhibitors like Anastrozole or Letrozole.

This rebound effect happens because these AIs suppress the production of estrogen, but once the AI is stopped, estrogen levels rise temporarily as the body's natural production resumes.

This abrupt rise in the body’s natural production of estrogen could lead to premature closure of growth plates, potentially impacting final height.

Missing a few doses of a non-steroidal Aromatase Inhibitors could cause that, so be careful when using one
rebound can be strongly reduced by tapering off slowly instead of stopping suddenly

but in comparison to exemestane, letrozole and Anastrozole are cheaper and better studied

My personal choice is Exemestane, because it has the least side effects and estrogen rebound isn't a thing
(but like I said, every AI works, just keep E2 at 15-20 pg/mL
and if youre using a non-steroidal one, be careful that you dont forget to take them)

DOSAGE PROTOCOLS AND BLOODWORK
Test your E2 to find the dosage you probably need
1 week into your Ai you should do another blood test to see if you should adjust the dose
You want to Target blood estradiol levels of 15–20 pg/mL and never go under 10 pg/mL
(for reference, normal estradiol levels for teenagers are around 20-50 pg/mL)

If you can't do blood tests, youre basically playing russian roulette, so be careful
in that scenario start a low dose, for example 6,25mg of Exemestane and adjust the dose slowly on how you feel and symptoms you experience

symptoms of low estrogen
Sudden joint pain/dryness
Drop in libido or morning erections
Brain fog, mood drop, irritability
Dry skin or hair shedding increase
Unexplained fatigue
if these occure, lower the dose immediately

symptoms of high estrogen
Puffy face/water retention
Fat gain on hips/chest
Gynecomastia or nipple sensitivity
Emotional volatility or crying easily
Chronic bloating
if these occure you should up the dose

Also, here is an overview, how much different dosages suppress your estrogen

Spoiler: suppression of estrogen

Anastrozole:
0.5 mg → ~50–60% E2 suppression
1 mg → ~80–85% E2 suppression
5 mg → ~85–90% E2 suppression (plateau)
Letrozole:
0.25 mg → ~60–65% E2 suppression
0.5 mg → ~75–80% E2 suppression
1 mg → ~85–90% E2 suppression
2.5 mg → ~90–95% E2 suppression
Exemestane:
6.25 mg → ~30–35% E2 suppression
12.5 mg → ~55–60% E2 suppression
25 mg → ~85–95% E2 suppression

Avoid over suppression (estrogen crash) and Monitor symptoms and do bloodwork.

BlOODWORK
(budget friendly)

Spoiler: Bloodwork - what to test

Test Estradiol (E2)
Why: Directly shows if your estrogen is in your target range (~15–20 pg/ml).
When:
before the start to calculate the dose you need and then check again 1 week after the start
If everything is correct check 1 month later to see if its stable
then every 8-10 weeks
Total Testosterone + Free Testosterone
Why: AI can raise testosterone; high T can cause secondary effects (acne, aggression, libido swings).
When: Same time as E2 checks.

SHBG (Sex Hormone Binding Globulin)
Why: AI-induced changes in T and E2 affect SHBG, which changes free T availability.
When: every 8-12 weeks Alongside T/E2 checks.

Lipid Panel (Total Cholesterol, LDL, HDL, Triglycerides)
Why: Low E2 can lower HDL and raise LDL → cardiovascular risk.
When: Every 3 months.

Liver Enzymes (ALT, AST)
Why: Ais is metabolized in the liver; rare but possible liver stress.
When: Every 3 months or if symptoms appear.
(important if you drink alcohol)

Bone Health (long-term)
Why: Chronically low E2 can reduce bone density.
When: DEXA scan after 12+ months if running AI long-term.
(optional, but would be good)

simply put together

the baseline test would be:
E2 (sensitive), Total T, Free T, SHBG, Lipid Panel, ALT/AST

around 1 week after AI start:
E2 (sensitive) (optional Total T)

then E2 (sensitive), Total T, Free T, SHBG
every 8-10 weeks and lipids + liver enzymes every 3 months

You can do blood tests in private labs

IMPORTANT NOTES AND TIPS
The time when you take your Ai is not important (should still be around the same time)
But taking your Ai with a meal is
(alternatively, you can take your ai with a tablespoon of olive oil)

Storage:
Dry location with an ideal temperature of 15–25°C and no sun exposure
(just put it in your drawer)

Hormones return to baseline within 2–4 weeks after you stop taking your ai

weird, but don't eat Grapefruits and don't drink Grapefruit Juice
Grapefruit and its juice contain compounds that block the liver enzyme CYP3A4, which helps break down many drugs, including aromatase inhibitors.
This blockage can cause the ai to build up in your blood, and with that increase the risk of side effects

CLINICAL STUDIES OF HEIGHT INCREASE WITH AIS
View attachment 4005487
STUDY https://ijpeonline.biomedcentral.com/articles/10.1186/1687-9856-2015-4

Aromatase inhibitors Alone
Boys with idiopathic short stature or delayed puberty treated with anastrozole (AI) showed around 5 cm increase in predicted adult height by delaying growth plate closure
STUDY https://pubmed.ncbi.nlm.nih.gov/16189252

Growth Hormone (HGH) Alone:
This study looked at kids with idiopathic short stature (ISS), meaning normal GH levels but short height.
HGH treatment increased adult height by an average of 4–6 cm compared to untreated children.
STUDY https://umraniyepediatri.com/storage/upload/pdfs/1732279204-en.pdf

Combination Therapy (AI + HGH):
combining growth hormone with aromatase inhibitors in adolescent boys with idiopathic short stature led to an average adult height increase of about 6 to 9 cm.
STUDY https://academic.oup.com/jcem/article/110/9/e2871/8125692?login=false

HOPEFUL
Boys grow 2.13 cm in average after the age of 18 without anything
a study shows, that on average, boys grew an additional 2.13 cm between ages 18 and 27, with some increasing by as much as 7 cm
absolutely hopeful study
STUDY https://pubmed.ncbi.nlm.nih.gov/6638938

AIS IN CONTEXT OF BODYBUILDING
View attachment 4007910
i dont want this topic to be left out completely, but i will just cover the most important things

because of higher testosterone levels, the body converts more testosterone to estrogen
Ais can help to control estrogen levels during steroid cycles,
preventing side effects like water retention, bloating, and gynecomastia.

They’re used to maintain a healthy testosterone-to-estrogen balance, which supports better muscle gains, mood, and overall performance.
Additionally, by limiting estrogen, AIs can reduce fat storage and help bodybuilders achieve a leaner, more defined physique.

When Ais come to play in bodybuilding
if your Estradiol is too high and you experience side effects like
-Gyno
-Water retention
-Severe acne
-Mood swings (irritability or depression)

At High Doses or for Estrogen-Sensitive Users
some users don't need one even with +500 mg test a week
while some require an AI even with just 250 mg/week
(At ~500 mg testosterone a week most need an AI)

During Contest Prep
Ais reduce water retention, many bodybuilders use that to achieve a more defined and dryer look

Post-Cycle therapy (PCT)
After a steroid cycle to restore natural testosterone production
Often combined with SERMs (Clomid, Nolvadex)

SPECIAL TOPICS
AI Resistance
true resistance to aromatase inhibitors in men is very rare, but possible
In bodybuilding “resistance” usually means underdosing,
poor absorption of the product, or genetic differences in aromatase activity

In practice:
If estrogen stays high despite seemingly adequate AI dosing,
first rule out fake/underdosed product and high androgen load before assuming true resistance

Many UGL AIs are underdosed
Buy from tested sources (Janoshik reports).
and see how much impact they have on your E2 via bloodwork

Myths about estrogen
Myth 1: “Lower estrogen = more muscle gains.”
Truth: Too little estrogen impairs strength, recovery, joint health, and IGF-1 signaling, all critical for muscle growth.

Myth 2: “Estrogen is bad for men and should be eliminated completely.”
Truth: Estrogen plays important roles in men, including bone haelth, brain function, and regulating libido

Myth 3: “If you don’t feel symptoms, your estrogen is fine.”
Truth: Some people have no noticeable symptoms until E2 is way out of range, that's why blood tests are so important
(for example, my E2 was at 56 pg/mL and i didn't notice anything)

CONCLUSION

Spoiler: conclusion

Ais work by lowering estrogen, which delays the closing of your growth plates, giving you more time to grow taller and with that
are a great tool that could give you another 1-6cm, depending on your bone age

(keep in mind that if youre 5'7 at 16 or older with a similar bone age, nothing except LL will bring you to 6'0)

The younger your bone age, the more you can grow through all of this

even tough they are different, the type of Ai you use doesnt really matter
but understanding how they work does

So, while AIs can help extend your growth window, they’re not some magic pill, get your bloodwork done and dont be a retard

if i forget anything you want to know, just tell me

other threads i strongly recommend reading

Spoiler: threads

Another guide on HGH + Ai
https://looksmax.org/threads/theore...omatase-inhibitor-for-pubertymaxxing.1061735/

Heightmaxxing experience with HGH + Ai
https://looksmax.org/threads/coveri...xperience-results-tips-and-struggles.1172898/

About HGH
https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

hope we all ascend
-renos

Spoiler: tags

@Zagro @Mainlander @MyDreamIsToBe183CM

​

When it comes to heightmaxxing people always recommend the combination of HGH and an AI
but what even are Aromatase Inhibitors?

This guide will teach you everything you need to know about Aromatase inhibitors!
read this guide if you want to gain knowledge about HGH → https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

THE ROLE OF ESTROGEN WHEN IT COMES TO HEIGHT
Human linear growth occurs at the epiphyseal (growth) plates of long bones, which are zones of cartilage undergoing endochondral ossification.
These plates consist of:
Resting zone: reserves of chondrocytes
Proliferative zone: active cell division
Hypertrophic zone: cell enlargement and mineralization

View attachment 4004032
So, bone lengthening continues until the growth plate closes, which marks the end of height increase.
This closure process is triggered by estrogen
How?
Estrogen closes growth plates by binding to estrogen receptor alpha on chondrocytes, pushing them to mature faster while depleting the reserve of stem-like cells that keep the plate active once these cells mature too quickly, the growth plate runs out of new cells that can make more bone length.

Estrogen also makes the plate release signals that pull in blood vessels, which bring bone building cells
These cells replace the last bits of cartilage with solid bone.
When that happens, the growth plate turns into a thin bony line, and you can’t get any taller.

So make sure your plates are open before you take action
you can confirm this through an x-ray of your hand or knee

Spoiler: open vs closed growth plates

View attachment 4008423

The younger your bone age, the more potential you have to grow
ideally it should be younger than 16, but even after that you could grow a few more cm

but once plates are closed, Limb lenghtening is the only way to increase height other than fixing posture and wearing shoe-lifts

WHAT ARE AROMATASE INHIBITORS?

Spoiler: history

The story starts back in the 1950s and 60s when scientists first figured out how estrogen is made in the body.
They realized that if you could block the aromatase enzyme, you could lower estrogen levels and potentially slow down some type of cancers

In the 1970s, the first aromatase inhibitors were developed. These early drugs, like aminoglutethimide, weren’t very selective and had a lot of side effects.
They worked by binding tightly to the enzyme and basically breaking it, but because they weren’t very specific, patients often had issues.

Then, during the 1980s and early 90s, researchers worked on making better inhibitors.
Nonsteroidal ones came along, such as fadrozole and vorozole, which were safer and more targeted.

The big breakthrough happened in the 1990s: anastrozole, letrozole, and exemestane were invented
These drugs were more effective, had fewer side effects, and became the new standard treatment for hormone-sensitive breast cancer
They’re still widely used today because they work well and patients tolerate them better than older drugs.

Aromatase inhibitors also come to play for treating male hypogonadism or delaying puberty
(and with that being able to grow for a longer period of time)

Aromatase inhibitors are compounds that block or kill the enzyme aromatase, which converts testosterone into estrogen.

Spoiler: what is aromatase

Aromatase is a cytochrome P450 enzyme, encoded bythe CYP19A1 gene.
It catalyzes the aromatization of the A-ring ofandrogens, specifically:
Testosterone into Estradiol and Androstenedione intoEstrone

(Estrogen refers to a group of hormones that include estradiol, estrone, and estriol, with estradiol being the most potent and prevalent)

By lowering estrogen levels, AIs can delay epiphyseal fusion, extending the window for longitudinal bone growth

The Aromatization Reaction (Biochemistry)
At the molecular level, aromatase performs a three-stepoxidation of the androgen substrate’s A-ring:
Hydroxylation of the 19-methyl group (C19).
Conversion to a formyl group.
Aromatization of the A-ring, forming an aromaticphenol (the hallmark of estrogen).

This process is NADPH-dependent, and localiezd in the endoplasmic reticulum of cells
By taking an aromatase inhibitor we can block this process leading to less estrogen

ANASTROZOLE, LETROZOLE AND EXEMESTANE IN COMPARISON
The main difference is that anastrozole and letrozole are non-steroidal aromatase inhibitors, while exemestane is a steroidal aromatase inhibitor.
Simply put, this means that anastrozole and letrozole anesthetize the aromatase enzyme while exemestane kills the aromatase enzyme
(The enzyme is reproduced by the body)

GENERAL COMPARISON​

Property	Anastrozole (Arimidex)	Letrozole (Femara)	Exemestane (Aromasin)
Type	Non-steroidal, reversible	Non-steroidal, reversible	Steroidal, irreversible
Estrogen Suppression	~50–70% (dose dependent)	~80–98% (very potent)	~65–85% (irreversible)
Half-Life	~48 hrs	~40–60 hrs	~24–27 hrs
Rebound Risk	Medium if stopped fast	High (sharp increase)	Low (enzyme destroyed)
Titration Precision	High (easy microdose)	Moderate to difficult	Low (fixed dose tabs)
Bone Impact	Mild (long-term)	moderate to severe	moderate
Lipid impact	Mild, but could affect HDL	Moderate to severe	moderate
Onset of Suppression	~24 hours	Within hours	~24 hours (stronger than Anastrozole)
Peak Suppression	~2–4 days	~2–3 days	~2–3 days

PRICES​

Source	Anastrozole Price (1mg)	Letrozole Price (2.5mg)	Exemestane Price (25mg)
Pharma (Brand)	$5–$10	$8–$15	$10–$20
Generic (Indian)	$0.50–$1.50	$1–$3	$1–$4
UGL (Chinese)	$0.20–$0.50	$0.30–$1	$0.30–$1

SIDE EFFECTS​

Side Effect	Anastrozole (Arimidex)	Letrozole (Femera)	Exemestane (Aromasin)
Hot flashes	Common	Common	Common
Joint pain	Moderate	Moderate to severe	Mild to moderate
Fatigue	Mild to moderate	Moderate	Mild to moderate
Bone density loss	Mild (long-term use)	More severe if misused	Moderate (monitor needed)
Nausea	Mild	Mild to moderate	Mild
Mood changes	Possible	Possible	Possible
Headache	Occasionally	Occasionally	Occasionally
Increased cholesterol	Mild	Moderate to severe	Moderate
Muscle pain	Mild	Moderate	Mild

Exemestane is harsher on hair because of its androgenic metabolite, 17-β-hydroxyexemestane.
I’d recommend adding something like ru58841 if you choose exemestane.
(That said, hair loss from exemestane only happens if you’re genetically prone to it)

Side effects like losing cognitive abilities only occur when your estrogen is under 10 pg/mL for a longer period of time
this and hair loss were the side effects I was afraid of the most, but as long as you know what youre doing, you don't have to worry about them

Here is a study that proves Ais are safe when it comes to influencing cognitive abilities
STUDY https://pubmed.ncbi.nlm.nih.gov/20421333

Also, Ais can increase levels of endogenous Testosterone production in men by 30-60% which is a lot

The biggest downside of non-steroidal Ai's is the possible estrogen rebound

Spoiler: estrogen rebound explained

Estrogen rebound is a phenomenon that occurs when the body experiences an increase in estrogen levels after discontinuing or reducing the dosage of aromatase inhibitors like Anastrozole or Letrozole.

This rebound effect happens because these AIs suppress the production of estrogen, but once the AI is stopped, estrogen levels rise temporarily as the body's natural production resumes.

This abrupt rise in the body’s natural production of estrogen could lead to premature closure of growth plates, potentially impacting final height.

Missing a few doses of a non-steroidal Aromatase Inhibitors could cause that, so be careful when using one
rebound can be strongly reduced by tapering off slowly instead of stopping suddenly

but in comparison to exemestane, letrozole and Anastrozole are cheaper and better studied

My personal choice is Exemestane, because it has the least side effects and estrogen rebound isn't a thing
(but like I said, every AI works, just keep E2 at 15-20 pg/mL
and if youre using a non-steroidal one, be careful that you dont forget to take them)

DOSAGE PROTOCOLS AND BLOODWORK
Test your E2 to find the dosage you probably need
1 week into your Ai you should do another blood test to see if you should adjust the dose
You want to Target blood estradiol levels of 15–20 pg/mL and never go under 10 pg/mL
(for reference, normal estradiol levels for teenagers are around 20-50 pg/mL)

If you can't do blood tests, youre basically playing russian roulette, so be careful
in that scenario start a low dose, for example 6,25mg of Exemestane and adjust the dose slowly on how you feel and symptoms you experience

symptoms of low estrogen
Sudden joint pain/dryness
Drop in libido or morning erections
Brain fog, mood drop, irritability
Dry skin or hair shedding increase
Unexplained fatigue
if these occure, lower the dose immediately

symptoms of high estrogen
Puffy face/water retention
Fat gain on hips/chest
Gynecomastia or nipple sensitivity
Emotional volatility or crying easily
Chronic bloating
if these occure you should up the dose

Also, here is an overview, how much different dosages suppress your estrogen

Spoiler: suppression of estrogen

Anastrozole:
0.5 mg → ~50–60% E2 suppression
1 mg → ~80–85% E2 suppression
5 mg → ~85–90% E2 suppression (plateau)
Letrozole:
0.25 mg → ~60–65% E2 suppression
0.5 mg → ~75–80% E2 suppression
1 mg → ~85–90% E2 suppression
2.5 mg → ~90–95% E2 suppression
Exemestane:
6.25 mg → ~30–35% E2 suppression
12.5 mg → ~55–60% E2 suppression
25 mg → ~85–95% E2 suppression

Avoid over suppression (estrogen crash) and Monitor symptoms and do bloodwork.

BlOODWORK
(budget friendly)

Spoiler: Bloodwork - what to test

Test Estradiol (E2)
Why: Directly shows if your estrogen is in your target range (~15–20 pg/ml).
When:
before the start to calculate the dose you need and then check again 1 week after the start
If everything is correct check 1 month later to see if its stable
then every 8-10 weeks
Total Testosterone + Free Testosterone
Why: AI can raise testosterone; high T can cause secondary effects (acne, aggression, libido swings).
When: Same time as E2 checks.

SHBG (Sex Hormone Binding Globulin)
Why: AI-induced changes in T and E2 affect SHBG, which changes free T availability.
When: every 8-12 weeks Alongside T/E2 checks.

Lipid Panel (Total Cholesterol, LDL, HDL, Triglycerides)
Why: Low E2 can lower HDL and raise LDL → cardiovascular risk.
When: Every 3 months.

Liver Enzymes (ALT, AST)
Why: Ais is metabolized in the liver; rare but possible liver stress.
When: Every 3 months or if symptoms appear.
(important if you drink alcohol)

Bone Health (long-term)
Why: Chronically low E2 can reduce bone density.
When: DEXA scan after 12+ months if running AI long-term.
(optional, but would be good)

simply put together

the baseline test would be:
E2 (sensitive), Total T, Free T, SHBG, Lipid Panel, ALT/AST

around 1 week after AI start:
E2 (sensitive) (optional Total T)

then E2 (sensitive), Total T, Free T, SHBG
every 8-10 weeks and lipids + liver enzymes every 3 months

You can do blood tests in private labs

IMPORTANT NOTES AND TIPS
The time when you take your Ai is not important (should still be around the same time)
But taking your Ai with a meal is
(alternatively, you can take your ai with a tablespoon of olive oil)

Storage:
Dry location with an ideal temperature of 15–25°C and no sun exposure
(just put it in your drawer)

Hormones return to baseline within 2–4 weeks after you stop taking your ai

weird, but don't eat Grapefruits and don't drink Grapefruit Juice
Grapefruit and its juice contain compounds that block the liver enzyme CYP3A4, which helps break down many drugs, including aromatase inhibitors.
This blockage can cause the ai to build up in your blood, and with that increase the risk of side effects

CLINICAL STUDIES OF HEIGHT INCREASE WITH AIS
View attachment 4005487
STUDY https://ijpeonline.biomedcentral.com/articles/10.1186/1687-9856-2015-4

Aromatase inhibitors Alone
Boys with idiopathic short stature or delayed puberty treated with anastrozole (AI) showed around 5 cm increase in predicted adult height by delaying growth plate closure
STUDY https://pubmed.ncbi.nlm.nih.gov/16189252

Growth Hormone (HGH) Alone:
This study looked at kids with idiopathic short stature (ISS), meaning normal GH levels but short height.
HGH treatment increased adult height by an average of 4–6 cm compared to untreated children.
STUDY https://umraniyepediatri.com/storage/upload/pdfs/1732279204-en.pdf

Combination Therapy (AI + HGH):
combining growth hormone with aromatase inhibitors in adolescent boys with idiopathic short stature led to an average adult height increase of about 6 to 9 cm.
STUDY https://academic.oup.com/jcem/article/110/9/e2871/8125692?login=false

HOPEFUL
Boys grow 2.13 cm in average after the age of 18 without anything
a study shows, that on average, boys grew an additional 2.13 cm between ages 18 and 27, with some increasing by as much as 7 cm
absolutely hopeful study
STUDY https://pubmed.ncbi.nlm.nih.gov/6638938

AIS IN CONTEXT OF BODYBUILDING
View attachment 4007910
i dont want this topic to be left out completely, but i will just cover the most important things

because of higher testosterone levels, the body converts more testosterone to estrogen
Ais can help to control estrogen levels during steroid cycles,
preventing side effects like water retention, bloating, and gynecomastia.

They’re used to maintain a healthy testosterone-to-estrogen balance, which supports better muscle gains, mood, and overall performance.
Additionally, by limiting estrogen, AIs can reduce fat storage and help bodybuilders achieve a leaner, more defined physique.

When Ais come to play in bodybuilding
if your Estradiol is too high and you experience side effects like
-Gyno
-Water retention
-Severe acne
-Mood swings (irritability or depression)

At High Doses or for Estrogen-Sensitive Users
some users don't need one even with +500 mg test a week
while some require an AI even with just 250 mg/week
(At ~500 mg testosterone a week most need an AI)

During Contest Prep
Ais reduce water retention, many bodybuilders use that to achieve a more defined and dryer look

Post-Cycle therapy (PCT)
After a steroid cycle to restore natural testosterone production
Often combined with SERMs (Clomid, Nolvadex)

SPECIAL TOPICS
AI Resistance
true resistance to aromatase inhibitors in men is very rare, but possible
In bodybuilding “resistance” usually means underdosing,
poor absorption of the product, or genetic differences in aromatase activity

In practice:
If estrogen stays high despite seemingly adequate AI dosing,
first rule out fake/underdosed product and high androgen load before assuming true resistance

Many UGL AIs are underdosed
Buy from tested sources (Janoshik reports).
and see how much impact they have on your E2 via bloodwork

Myths about estrogen
Myth 1: “Lower estrogen = more muscle gains.”
Truth: Too little estrogen impairs strength, recovery, joint health, and IGF-1 signaling, all critical for muscle growth.

Myth 2: “Estrogen is bad for men and should be eliminated completely.”
Truth: Estrogen plays important roles in men, including bone haelth, brain function, and regulating libido

Myth 3: “If you don’t feel symptoms, your estrogen is fine.”
Truth: Some people have no noticeable symptoms until E2 is way out of range, that's why blood tests are so important
(for example, my E2 was at 56 pg/mL and i didn't notice anything)

CONCLUSION

Spoiler: conclusion

Ais work by lowering estrogen, which delays the closing of your growth plates, giving you more time to grow taller and with that
are a great tool that could give you another 1-6cm, depending on your bone age

(keep in mind that if youre 5'7 at 16 or older with a similar bone age, nothing except LL will bring you to 6'0)

The younger your bone age, the more you can grow through all of this

even tough they are different, the type of Ai you use doesnt really matter
but understanding how they work does

So, while AIs can help extend your growth window, they’re not some magic pill, get your bloodwork done and dont be a retard

if i forget anything you want to know, just tell me

other threads i strongly recommend reading

Spoiler: threads

Another guide on HGH + Ai
https://looksmax.org/threads/theore...omatase-inhibitor-for-pubertymaxxing.1061735/

Heightmaxxing experience with HGH + Ai
https://looksmax.org/threads/coveri...xperience-results-tips-and-struggles.1172898/

About HGH
https://looksmax.org/threads/hgh-101-everything-you-need-to-know.1423722/

hope we all ascend
-renos

Spoiler: tags

@Zagro @Mainlander @MyDreamIsToBe183CM

​

Good post, but Anastrozole and other AIs can be dangerous after you stop using them, so you should take a milder form of an AI. My advice is Exemestane. It's what I personally use, and I can say that I haven't noticed any side effects. I usually take around 13.5 mg; the maximum I've taken is 25 mg. So be careful to avoid bad consequences, lol