Estrogen, Aromatize Inhibitors and Gynecomastia

Estrogen, Aromatize Inhibitors and Gynecomastia

The key take home points:

  • For optimal body composition, you want a high testosterone:estrogen ratio
  • High estrogen levels can cause side effects like water retention, acne and gynecomastia
  • Aromasin is the best choice for an aromatize inhibitor (AI)

Related - The Best Estrogen and Cortisol Control

Testosterone and Estrogen

Testosterone is the primary male sex hormone. Estrogen is the primary sex hormone. For optimal body composition, you want as high of a testosterone:estrogen ratio as possible.

However, don’t think estrogen is all bad. Some estrogen is needed to sensitize the androgen receptor. Estrogen is a hormone that you don’t want eliminate completely, you just want to keep it in the normal range at all times.

High estrogen levels in men can lead to side effects like gynecomastia, water retention, acne, lack of sex drive and increased body fat (particularly around the mid-section. High estrogen levels in females will cause the same side effects, but just to a lesser extent since the hormone already occurs in high concentrations in their bodies naturally.

The only way to truly determine what your estrogen levels are is through blood work. It will be listed as an estrodial or E2 test on the blood requisition form.

Aromatize Inhibitors

Whenever using steroids, you want to use an aromatize inhibitor (AI) to prevent testosterone from converting into estrogen. This will prevent yourself from high estrogen related side effects and increase free testosterone levels.

There is a big misconception that an AI will hinder gains. That is completely not true. High estrogen levels can lead to side effects like water retention and bloating.

If you were to run a steroid cycle without an aromatize inhibitor, you would gain more scale weight then running the same steroid cycle with an aromatize inhibitor, but that increase in scale weight is not muscle. It’s simply water retention from the high estrogen levels.

You always want to start your aromatize inhibitor on day one of your cycle, and to run it throughout your entire cycle and post cycle therapy (PCT). The whole point of an aromatize inhibitor is to prevent side effects before they occur. Once the side effects have occurred, it’s already too late.

Aromasin (exemestane)

Aromasin (exemestane) is the best choice for an aromatize inhibitor since it is a suicide aromatize inhibitor. What that means is that there will be no estrogen rebound when you discontinue usage.

The standard recommended dosage of aromasin is 10-12.5mg every other day.

Arimidex (anastrozole)

Arimidex (anastrozole) can also be used as an aromatize inhibitor but it is not as good of a choice as aromasin since there will be a small estrogen rebound when you discontinue usage. You can use arimidex as your AI, you will just need to slowly taper off your dosage.

The standard recommended dosage of arimidex is 0.5mg every other day.

Letrozole (femara)

Letrozole (femara) should not be used. It is the strongest aromatize inhibitor available and will crush estrogen levels to zero.

Letrozole should only be used as a last resort if you are experiencing a gynocamestia flair up. Under normal conditions, you will never need to use letrozole. It is only needed because someone is experiencing side effects from improper steroid usage.

Natural anti-estrogen supplements

If you feel that you naturally have high estrogen levels, natural anti-estrogen supplements like DIM (diindolylmethane), chrysin (5,7-Dihydroxyflavone), Apigenin do work and are very effective, but they are not strong enough to provide estrogen support when using actual steroids. A real AI such as aromasin or arimidex is needed whenever using androgens.

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jeff gray - December 4, 2017


David Miller - December 1, 2017

I personally find arimidex works better for myself , although its possible all exemestane I’ve tried was bunk.

Dustin Nutt - December 1, 2017

Is this true even at low doses of testosterone for TRT putting the body back into normal/high normal range?

Chris Lee - November 30, 2017

Learned a lot here.. not gonna be doing any cycles aby time soon just gonna go on trt if needed from doctor when get blood work back .. thanks for the info

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