Causes of Gynecomastia

what causes gynecomastia

What causes man boobs? In one form or another, we field this question over and over in online discussions on and in our consultation room in New York City. Gynecomastia sufferers sometimes seem almost desperate to know what’s behind their condition – undoubtedly so they can begin to figure out what to do about it.

Except for occasional cases in which excess fat alone is the culprit, most cases of gynecomastia are triggered by a hormonal imbalance: too much estrogen, not enough testosterone or both. You probably know that these hormones govern the development of female and male traits. What you may not know is that men produce estrogen as well as testosterone, albeit at much lower levels than women do. Hormone levels for men can become “out of whack,” as we sometimes say for short, and man boobs can be the result.

Hormone levels change during puberty, obviously. Some young men develop gynecomastia during their teen years and many lucky adolescents see their moobs shrink as they get older.

You may have heard that some drugs can cause gynecomastia. This is true of some prescription medications, such as antidepressants and cancer drugs, as well as street drugs like anabolic steroids and possibly marijuana. In this case, hormones again are the underlying culprits as many drugs cause changing hormone levels in the body.

Hormones are also the bottom line when it comes to health conditions that contribute to gynecomastia. Kidney failure, liver failure, some tumors and even malnutrition can contribute to fluctuating hormones and are potential factors in the development of enlarged male breasts.

Today, there’s a lot we know about gynecomastia, including the way hormones are involved. There are also some aspects of the condition we don’t yet understand. For instance, because it’s so common for men to experience fluctuating hormone levels at various times in their lives, why don’t more men develop lasting gynecomastia? It could very well be that there’s a genetic aspect to the condition that hasn’t yet been identified.

If you’d like some help in understanding your particular case, you can contact our office in New York City. Or visit a gynecomastia forum like and join the discussion.

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