Testosterone Therapy and High Estrogen in Men

Testosterone optimisation therapy represents an exciting prospect for men who’ve been suffering from low testosterone.

And while the benefits of testosterone therapy are numerous, side effects are still a matter of course with any drugs or medical treatment. Although, when done properly the side effects of testosterone optimisation therapy are minimal.

Nevertheless, in spite of this there is still one potential side effect that scares men more than any other:

High estrogen.

Ironically, the prospect of testicular shrinkage or reduced sperm count from TOT doesn’t seem to bother most men. But the thought of high estrogen side effects from testosterone makes most men want to run for the hills.

In fact, so many are scared of high estrogen that they will avoid testosterone therapy altogether – even though they desperately need it.

Testosterone and the Symptoms of High Estrogen in Men

I get questions on a daily basis from men fretting about the high estrogen side effects from testosterone therapy. Let’s get one thing straight:

Undergoing TOT does not automatically mean you will suffer from high estrogen.

And you must remember that everyone is biochemically unique.

That’s why hormone optimisation is both an art and science. There is no one size fits all approach.

Nevertheless, it pays to be vigilant because high estrogen side effects in men can be nasty. Typical symptoms of high estrogen in men on testosterone therapy can vary, but these are some of the most common:

  • Water retention. Water retention, puffiness or colliquially known as ‘moon face’ can sometimes occur as a side effect of high estrogen.
  • Poor erection quality and low libido. Estradiol plays a crucial role in libido and erectile function. However, too much estradiol can cause weak erections and lower your libido.
  • Moodiness. High estrogen can cause mood swings and emotional outbursts. Crying spontaneously and bouts of depression can become the norm.
  • Gynaecomastia. Gynaecomastia or ‘man boobs’ is an unsightly side effect of high estrogen in men. This involves the growth of excess fat and glandular tissue around the breast. But this is not an overnight phenomenon and tends to occur in stages. It usually starts out with nipple swelling a

If you already have high estradiol (estrogen) levels prior to testosterone therapy, it’s likely the introduction of testosterone will elevate your estradiol levels further. This is due to the aromatisation of testosterone into estradiol.

The side effects of high estrogen can be mitigated and avoided altogether by diligent blood work and proper estrogen management. By estrogen management I refer to increased injection frequency to mitigate the conversion of testosterone into estradiol or the use of an aromatase inhibitor.

As a side note, I injected frequently and did all the right things, including having a low level of body fat. However, this did not prevent me from having high levels of estradiol.

I used to be quite vehemently against aromatase inhibitors. But after trying a conservative dose (0.5mg every 5 days), I can say that my mood has dramatically improved and I feel much less emotional / ratty.

High estrogen symptoms - moodiness

The use of an aromatase inhibitor should be considered when there is a clinical need – i.e. your estradiol levels are high and you have the symptoms of high estrogen.

Final Thoughts

Estrogen is NOT the enemy.

Estrogen plays a pivotal role in the male body. Among other things, it’s responsible for modulating libido, erectile strength and bone mineral density

Homeostasis is a finely tuned system of checks and balances. So, if you’re chasing lab numbers because you read about it on some forum, then you are playing with fire.  If one guy feels good at X level, doesn’t necessarily mean you will too.

Blood work is to critical in evaluating your response to treatment. But remember – with testosterone optimisation therapy how you FEEL is foremost and lab numbers are secondary.

Usually, the best indicator that your estrogen levels are in order is the absence of symptoms.

There’s no doubt, high estrogen in men can be problematic. However, driving your estrogen down too low through aromatase inhibitors can tank your libido. As a result, you’ll feel like a eunuch and you’ll have to wait for it to return.

Not a pleasant experience.

But here’s another thing:

Some days your libido may be less than others – just like before you started testosterone therapy.

That’s life!

It doesn’t mean that high estrogen has ruined your testosterone therapy and your life.

Testosterone improves your libido, but doesn’t turn you into a sex machine who’s always ‘on.’ So don’t assume because your sex drive is lower on any given day that estrogen is to blame and now you need to start taking an AI!!

Remember – when it comes to hormone optimisation, an assumption without blood work is just pissing in the wind.


If you want to understand estrogen management at a high level, I recommend you listen to this podcast. In this podcast Jay Campbell and Dr John Crisler really dive deep into the subject. Dr John Crisler, one of the best in the testosterone optimisation game, gives a very high level overview of estrogen control methods.

PS. Be sure to check out Jay Campbell’s new book – the Testosterone Optimization Bible: The Ultimate Guide to Living an Optimized Life. In there you’ll find everything you need to know on hormone optimization and on estrogen management.


Michael Schulster, Aaron M Bernie, Ranjith Ramasamy.The role of estradiol in male reproductive function. Asian J Androl. 2016 May-Jun; 18(3): 435–440.