A guide to understanding AIs (Aromatase Inhibitors) (high effort post)

mo6

mo6

5‘5 with big dreams
Joined
Nov 28, 2025
Posts
129
Reputation
72
So how do AI‘s work and what are they used for? Aromatase is an enzyme (CYP19A1) that converts androgens into estrogens:
Testosterone into Estradiol (E2)
Androstenedione into Estrone (E1)
The enzyme is mainly found in:
Fat tissue, liver, brain, muscle and ovaries/testes
AIs block this enzyme which leads to:
Reduced estrogen production
Less conversion of testosterone into estrogen
A increase in testosterone
They don’t create testosterone, they prevent its conversion.
There are three types of AIs:
Non-steroidal AIs, these are Anastrozole, Lestrozole, Fadrozole, Vorozole, Rogletimide, CGS 20267 and YM511.
Steroidal AIs, also called Suicide Inhibitors, these are Exemestane, Formestane, Testolactone, Atamestane, 4-Hydroxyandrostenedione, 6-Methylenandrostenedione and Androstatrienedione.
Special AIs, which is only Aminoglutethimide.
So what are they used for in looksmaxxing?
Mostly for workout purposes.
Less estrogen leads to less water retention which makes muscles appear more.
Estrogen also influences where fat is stored, which is mainly the chest, the hips and the lower abdomen. With reduced estrogen fat distribution shifts to other parts of the body.
It increases androgen prominence which leads to a harder more masculine look.
So these effects are basically just changing the appearance of your body and they mostly go back after stopping the consumption of AIs.
Now to the negative side effects of AIs:
Your estrogen protects your joints, improves tendon elasticity and reduces inflammation.
Now without enough estrogen joint stiffness increases, training quality may decline and progression can suffer.
Now how do I decide which AI I to choose from? So many different options but what is best for you? Let me help you:
The choice is not about which AI is the best, but which AI fits you best. There are 3 main AIs to choose from I would say. These are Letrozole, Anastrozole and Exemestane.
This decision is based on:
reversibility vs. irreversibility
strength of estrogen suppression
stability vs. flexibility
side effects
clinical context
Reversible vs. Irreversible Inhibition:
Non-steroidal AIs are reversible
Steroidal AIs are irreversible
Strength of Estrogen Suppression:
Letrozole: very strong
Anastrozole: moderate to strong
Exemestane: moderate, gradual
Stronger suppression increased the risk of side effects and leaves less margin for error.
Estrogen Rebound Risk:
Reversible AIs have a higher rebound risk if treatment stops abruptly.
Irreversible AIs have a lower rebound risk, making them better for stable long-term effects.
Side-Effect Profile and Long-Term Tolerance:
Non-steroidal AIs can cause more abrupt hormonal shifts and impact joints or lipid profile more noticeably.
Steroidal AIs are usually smoother, sometimes slightly androgenic, and often better tolerated over time.
Control vs. Predictability Trade-Off
If you want rapid adjustment and reversibility, non-steroidal is preferred.
If you want stability and minimal fluctuations, then steroidal is preferred.
Clinical context is key:
In medicine, the choice is based on blood markers (estradol, LH, FSH), symptoms, goals, duration and individual response.

HOPE THIS THREAD HELPS SINCE I PUT A LOT OF TIME IN IT!
 
  • +1
Reactions: Sujumh, Ascensionsoon, 2uul and 6 others
¿Cómo funcionan los IA y para qué se utilizan? La aromatasa es una enzima (CYP19A1) que convierte los andrógenos en estrógenos.
Testosterona en estradiol (E2)
Androstenediona en estrona (E1)
La enzima se encuentra principalmente en:
Tejido graso, hígado, cerebro, músculo y ovarios/testículos
Los IA bloquean esta enzima, lo que provoca:
Reducción de la producción de estrógenos
Menor conversión de testosterona en estrógeno
Un aumento de la testosterona
No crean testosterona, impiden su conversión.
Hay tres tipos de IA:
Los IA no esteroides son Anastrozol, Lestrozol, Fadrozol, Vorozol, Rogletimida, CGS 20267 y YM511.
Los IA esteroides, también llamados inhibidores del suicidio, son exemestano, formestano, testolactona, atamestano, 4-hidroxiandrostenediona, 6-metilenandrostenediona y androstatrienediona.
IA especiales, que son solo aminoglutetimida.
Entonces, ¿para qué se utilizan en looksmaxxing?
Principalmente para fines de entrenamiento.
Menos estrógeno conduce a una menor retención de agua, lo que hace que los músculos parezcan más grandes.
El estrógeno también influye en la ubicación donde se almacena la grasa, principalmente en el pecho, las caderas y la parte inferior del abdomen. Al reducirse los niveles de estrógeno, la distribución de la grasa se desplaza a otras partes del cuerpo.
Aumenta la prominencia de andrógenos lo que conduce a una apariencia más dura y masculina.
Entonces, estos efectos básicamente cambian la apariencia de tu cuerpo y generalmente regresan después de dejar de consumir IA.
Ahora, en cuanto a los efectos secundarios negativos de las IA:
El estrógeno protege las articulaciones, mejora la elasticidad de los tendones y reduce la inflamación.
Ahora bien, sin suficiente estrógeno aumenta la rigidez de las articulaciones, la calidad del entrenamiento puede disminuir y la progresión puede verse afectada.
¿Cómo decido qué IA elegir? Hay tantas opciones, pero ¿cuál es la mejor para ti? Déjame ayudarte:
La elección no se trata de qué IA es la mejor, sino de cuál se adapta mejor a ti. Diría que hay tres IA principales para elegir: letrozol, anastrozol y exemestano.
Esta decisión se basa en:
reversibilidad vs. irreversibilidad
fuerza de la supresión de estrógenos
estabilidad vs. flexibilidad
efectos secundarios
contexto clínico
Inhibición reversible vs. irreversible:
Los IA no esteroides son reversibles
Los IA esteroides son irreversibles
Fuerza de la supresión de estrógenos:
Letrozol: muy fuerte
Anastrozol: moderado a fuerte
Exemestano: moderado, gradual
Una supresión más fuerte aumenta el riesgo de efectos secundarios y deja menos margen de error.
Riesgo de rebote de estrógeno:
Los IA reversibles tienen un mayor riesgo de rebote si el tratamiento se interrumpe abruptamente.
Las IA irreversibles tienen un menor riesgo de rebote, lo que las hace mejores para obtener efectos estables a largo plazo.
Perfil de efectos secundarios y tolerancia a largo plazo:
Los IA no esteroides pueden provocar cambios hormonales más abruptos e impactar las articulaciones o el perfil lipídico de manera más notable.
Los IA esteroides suelen ser más suaves, a veces ligeramente androgénicos y, a menudo, mejor tolerados con el tiempo.
Control vs. previsibilidad: ¿cómo se compensa?
Si desea un ajuste rápido y reversibilidad, se prefiere el tratamiento no esteroideo.
Si desea estabilidad y fluctuaciones mínimas, entonces se prefieren los esteroides.
El contexto clínico es clave:
En medicina, la elección se basa en marcadores sanguíneos (estradol, LH, FSH), síntomas, objetivos, duración y respuesta individual.

¡ESPERO QUE ESTE HILO TE AYUDE YA QUE LE DEDIQUÉ MUCHO TIEMPO!
good thread
 
  • +1
Reactions: mo6
1765659020702
 
  • +1
Reactions: JAYCELL, Grievous and Ray0n
formatting is bad, but the thread is good
 
  • +1
Reactions: mo6
So how do AI‘s work and what are they used for? Aromatase is an enzyme (CYP19A1) that converts androgens into estrogens:
Testosterone into Estradiol (E2)
Androstenedione into Estrone (E1)
The enzyme is mainly found in:
Fat tissue, liver, brain, muscle and ovaries/testes
AIs block this enzyme which leads to:
Reduced estrogen production
Less conversion of testosterone into estrogen
A increase in testosterone
They don’t create testosterone, they prevent its conversion.
There are three types of AIs:
Non-steroidal AIs, these are Anastrozole, Lestrozole, Fadrozole, Vorozole, Rogletimide, CGS 20267 and YM511.
Steroidal AIs, also called Suicide Inhibitors, these are Exemestane, Formestane, Testolactone, Atamestane, 4-Hydroxyandrostenedione, 6-Methylenandrostenedione and Androstatrienedione.
Special AIs, which is only Aminoglutethimide.
So what are they used for in looksmaxxing?
Mostly for workout purposes.
Less estrogen leads to less water retention which makes muscles appear more.
Estrogen also influences where fat is stored, which is mainly the chest, the hips and the lower abdomen. With reduced estrogen fat distribution shifts to other parts of the body.
It increases androgen prominence which leads to a harder more masculine look.
So these effects are basically just changing the appearance of your body and they mostly go back after stopping the consumption of AIs.
Now to the negative side effects of AIs:
Your estrogen protects your joints, improves tendon elasticity and reduces inflammation.
Now without enough estrogen joint stiffness increases, training quality may decline and progression can suffer.
Now how do I decide which AI I to choose from? So many different options but what is best for you? Let me help you:
The choice is not about which AI is the best, but which AI fits you best. There are 3 main AIs to choose from I would say. These are Letrozole, Anastrozole and Exemestane.
This decision is based on:
reversibility vs. irreversibility
strength of estrogen suppression
stability vs. flexibility
side effects
clinical context
Reversible vs. Irreversible Inhibition:
Non-steroidal AIs are reversible
Steroidal AIs are irreversible
Strength of Estrogen Suppression:
Letrozole: very strong
Anastrozole: moderate to strong
Exemestane: moderate, gradual
Stronger suppression increased the risk of side effects and leaves less margin for error.
Estrogen Rebound Risk:
Reversible AIs have a higher rebound risk if treatment stops abruptly.
Irreversible AIs have a lower rebound risk, making them better for stable long-term effects.
Side-Effect Profile and Long-Term Tolerance:
Non-steroidal AIs can cause more abrupt hormonal shifts and impact joints or lipid profile more noticeably.
Steroidal AIs are usually smoother, sometimes slightly androgenic, and often better tolerated over time.
Control vs. Predictability Trade-Off
If you want rapid adjustment and reversibility, non-steroidal is preferred.
If you want stability and minimal fluctuations, then steroidal is preferred.
Clinical context is key:
In medicine, the choice is based on blood markers (estradol, LH, FSH), symptoms, goals, duration and individual response.

HOPE THIS THREAD HELPS SINCE I PUT A LOT OF TIME IN IT!
nice thread but work on ur formatting that is horror
 
  • +1
Reactions: el hit and mo6
Effort thread but no citation to literature
 
  • +1
Reactions: mo6
Don’t worry it has nothing to do with you it was a very good thread tag me in the next one pls
Ty man will for sure do, also have a big thread on the holy trinity of hair growth: minoxidil, dutasteride and finasteride. If you wanna have a look into that I can tag you if you want?
 
  • +1
Reactions: Aryan Incel
So how do AI‘s work and what are they used for? Aromatase is an enzyme (CYP19A1) that converts androgens into estrogens:
Testosterone into Estradiol (E2)
Androstenedione into Estrone (E1)
The enzyme is mainly found in:
Fat tissue, liver, brain, muscle and ovaries/testes
AIs block this enzyme which leads to:
Reduced estrogen production
Less conversion of testosterone into estrogen
A increase in testosterone
They don’t create testosterone, they prevent its conversion.
There are three types of AIs:
Non-steroidal AIs, these are Anastrozole, Lestrozole, Fadrozole, Vorozole, Rogletimide, CGS 20267 and YM511.
Steroidal AIs, also called Suicide Inhibitors, these are Exemestane, Formestane, Testolactone, Atamestane, 4-Hydroxyandrostenedione, 6-Methylenandrostenedione and Androstatrienedione.
Special AIs, which is only Aminoglutethimide.
So what are they used for in looksmaxxing?
Mostly for workout purposes.
Less estrogen leads to less water retention which makes muscles appear more.
Estrogen also influences where fat is stored, which is mainly the chest, the hips and the lower abdomen. With reduced estrogen fat distribution shifts to other parts of the body.
It increases androgen prominence which leads to a harder more masculine look.
So these effects are basically just changing the appearance of your body and they mostly go back after stopping the consumption of AIs.
Now to the negative side effects of AIs:
Your estrogen protects your joints, improves tendon elasticity and reduces inflammation.
Now without enough estrogen joint stiffness increases, training quality may decline and progression can suffer.
Now how do I decide which AI I to choose from? So many different options but what is best for you? Let me help you:
The choice is not about which AI is the best, but which AI fits you best. There are 3 main AIs to choose from I would say. These are Letrozole, Anastrozole and Exemestane.
This decision is based on:
reversibility vs. irreversibility
strength of estrogen suppression
stability vs. flexibility
side effects
clinical context
Reversible vs. Irreversible Inhibition:
Non-steroidal AIs are reversible
Steroidal AIs are irreversible
Strength of Estrogen Suppression:
Letrozole: very strong
Anastrozole: moderate to strong
Exemestane: moderate, gradual
Stronger suppression increased the risk of side effects and leaves less margin for error.
Estrogen Rebound Risk:
Reversible AIs have a higher rebound risk if treatment stops abruptly.
Irreversible AIs have a lower rebound risk, making them better for stable long-term effects.
Side-Effect Profile and Long-Term Tolerance:
Non-steroidal AIs can cause more abrupt hormonal shifts and impact joints or lipid profile more noticeably.
Steroidal AIs are usually smoother, sometimes slightly androgenic, and often better tolerated over time.
Control vs. Predictability Trade-Off
If you want rapid adjustment and reversibility, non-steroidal is preferred.
If you want stability and minimal fluctuations, then steroidal is preferred.
Clinical context is key:
In medicine, the choice is based on blood markers (estradol, LH, FSH), symptoms, goals, duration and individual response.

HOPE THIS THREAD HELPS SINCE I PUT A LOT OF TIME IN IT!
@Sujumh
 
  • +1
Reactions: Sujumh
So how do AI‘s work and what are they used for? Aromatase is an enzyme (CYP19A1) that converts androgens into estrogens:
Testosterone into Estradiol (E2)
Androstenedione into Estrone (E1)
The enzyme is mainly found in:
Fat tissue, liver, brain, muscle and ovaries/testes
AIs block this enzyme which leads to:
Reduced estrogen production
Less conversion of testosterone into estrogen
A increase in testosterone
They don’t create testosterone, they prevent its conversion.
There are three types of AIs:
Non-steroidal AIs, these are Anastrozole, Lestrozole, Fadrozole, Vorozole, Rogletimide, CGS 20267 and YM511.
Steroidal AIs, also called Suicide Inhibitors, these are Exemestane, Formestane, Testolactone, Atamestane, 4-Hydroxyandrostenedione, 6-Methylenandrostenedione and Androstatrienedione.
Special AIs, which is only Aminoglutethimide.
So what are they used for in looksmaxxing?
Mostly for workout purposes.
Less estrogen leads to less water retention which makes muscles appear more.
Estrogen also influences where fat is stored, which is mainly the chest, the hips and the lower abdomen. With reduced estrogen fat distribution shifts to other parts of the body.
It increases androgen prominence which leads to a harder more masculine look.
So these effects are basically just changing the appearance of your body and they mostly go back after stopping the consumption of AIs.
Now to the negative side effects of AIs:
Your estrogen protects your joints, improves tendon elasticity and reduces inflammation.
Now without enough estrogen joint stiffness increases, training quality may decline and progression can suffer.
Now how do I decide which AI I to choose from? So many different options but what is best for you? Let me help you:
The choice is not about which AI is the best, but which AI fits you best. There are 3 main AIs to choose from I would say. These are Letrozole, Anastrozole and Exemestane.
This decision is based on:
reversibility vs. irreversibility
strength of estrogen suppression
stability vs. flexibility
side effects
clinical context
Reversible vs. Irreversible Inhibition:
Non-steroidal AIs are reversible
Steroidal AIs are irreversible
Strength of Estrogen Suppression:
Letrozole: very strong
Anastrozole: moderate to strong
Exemestane: moderate, gradual
Stronger suppression increased the risk of side effects and leaves less margin for error.
Estrogen Rebound Risk:
Reversible AIs have a higher rebound risk if treatment stops abruptly.
Irreversible AIs have a lower rebound risk, making them better for stable long-term effects.
Side-Effect Profile and Long-Term Tolerance:
Non-steroidal AIs can cause more abrupt hormonal shifts and impact joints or lipid profile more noticeably.
Steroidal AIs are usually smoother, sometimes slightly androgenic, and often better tolerated over time.
Control vs. Predictability Trade-Off
If you want rapid adjustment and reversibility, non-steroidal is preferred.
If you want stability and minimal fluctuations, then steroidal is preferred.
Clinical context is key:
In medicine, the choice is based on blood markers (estradol, LH, FSH), symptoms, goals, duration and individual response.

HOPE THIS THREAD HELPS SINCE I PUT A LOT OF TIME IN IT!
@Kevla my thread on AIs and which AI to choose, because you asked in your post
 

Similar threads

Aryan Incel
Replies
72
Views
2K
swordsinsanee
swordsinsanee
zentro
Replies
10
Views
404
wannabemogger
W
guts3
Replies
31
Views
370
sr3nn
S
rotation
Replies
33
Views
2K
obell5367
O

Users who are viewing this thread

  • BrownTriad
Back
Top