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Gynecomastia Causes (What are the Main Causes of Gyno)

When it comes to gynecomastia there can be a whole handful of reasons why the condition may occur. This overview is meant to help you understand what the main causes of gynecomastia are, and why you may be experiencing it for yourself.

Read on to learn all about these gyno causes and how they relate to you.

What Are The Causes Of Gynecomastia?

Although there are many conditions, medications and/or other substances that can lead to the development of gynecomastia, many of these boil down to one thing: hormonal imbalance.

Gynecomastia is, in essence, an excess of estrogen, a lack of testosterone, or a combination of both. When thinking about how to get rid of gynecomastia, it’s important to bear this in mind.

The defining characteristic of gynecomastia is the enlargement of male breasts, and may be caused by this imbalance.

It should also be noted that in many cases, causes of gynecomastia are unknown. In these cases, hormonal imbalance may not be the driving factor.

Learn More: What is Gynecomastia

With that said, let’s look at the various potential causes of gynecomastia, and why this may be occurring in your life:

  • Infancy: a male baby may suffer short-term gynecomastia as a result of the remaining estrogen from his mother still in his system. The condition generally resolves on its own.
  • Adolescence: the hormonal changes brought about by puberty can cause temporary gynecomastia. The problem generally resolves itself within six months to two years.
  • Substance Abuse: alcohol, methamphetamine, marijuana, heroin and methadone abuse.
  • Medications: many kinds of medication including anti-androgens, HIV treatments, anabolic steroids, anti-anxiety and anti-psychotic meds, chemotherapy, ulcer medication, heart medication and certain antibiotics.
  • Aging: aging leads to a progressive drop-off in testosterone levels in men, and is common over the age of 50.
  • Anabolic Steroids: steroids can increase the amount of testosterone, but the body may respond by converting excess testosterone into estrogen.
  • High Body Fat %: this can lead to increased fat storage in the chest (see note below), and higher levels of estrogen.
  • Underlying Health Conditions: several health conditions can cause or exacerbate gynecomastia. These include hypogonadism, aging, certain cancers, hyperthyroidism, kidney/liver failure, cirrhosis, and malnutrition/starvation.

It is very important to note that man boobs can ALSO be caused by excess fat in the breast. This can be a standalone issue, or more frequently an issue in combination with the excess breast gland tissue. If you happen to just have excess fat in your chest, true gynecomastia causes will not be the main culprit.

With that said, let’s dive into more details about the main causes of true gynecomastia:

Infancy and Puberty

Both infant boys and those who are entering puberty can develop temporary cases of gynecomastia.

The former is caused by lingering excess estrogen from the mother’s body, and quickly resolves itself in a matter of months. The latter is caused by the inevitable hormonal upheaval that happens during puberty, and resolves within 6 months to 2 years.

This may come as small comfort to a teenage boy, however, who already feels awkward and embarrassed about changes to his body, and may wish to find some solution to the condition.

Gynecomastia is common in pubescent assigned-male-at-birth individuals. As many as 60% will have some signs of the condition by the age of 14, largely due to the hormonal changes we all undergo during puberty.

This is a perfectly normal stage of puberty, and the symptoms will usually resolve themselves within two years.

Gynecomastia Children

Substance Abuse

The excessive use of certain substances can lead to cases of gynecomastia. Such substances include heroin, methadone, marijuana, methamphetamine, and other members of the amphetamine family.

Alcoholism

Alcoholism is, obviously, another form of substance abuse. It’s one that’s much more prevalent than illegal substance abuse.

Beer is a particular factor in this, because it’s packed with plant-based compounds called phytoestrogens. These compounds are so named because they mimic the effects of estrogen.

Though it hasn’t been definitively proven, some scientists believe that excess phytoestrogen can lead to similar effects to that of excesses of true estrogen.

Prescription Medications

Many cases of gynecomastia can be attributed to the use of prescription medications. These include:

  • Ulcer medications
  • HIV medications
  • Antipsychotics
  • Antidepressants
  • Certain heart disease medications
  • Antiandrogens
  • Hypertension medications

Check with your doctor if using these medications may lead to a reduction in testosterone or an increase in estrogen production. If so, that’s not a reason not to take your medication; it’s simply better to be prepared and to take steps accordingly.

Gynecomastia Pills

Aging

Aging leads to a progressive drop-off in testosterone levels in men. This starts at around the age of 30 and continues throughout the rest of your life.

Over-50s are particularly at risk of developing gynecomastia; as much as 65% of men in this group will develop gynecomastia.

Anabolic Steroids

Gynecomastia is often observed in professional bodybuilders for one simple reason: the use of anabolic steroids.

These steroids promote the production of testosterone. In turn the body may respond by converting excess testosterone into estrogen. This leads to gynecomastia in many cases.

Gynecomastia Steroids

High Body Fat Percentage

High body fat leads to higher rates of gynecomastia in two ways: increased fat storage in the chest (increased fat issue), and higher levels of estrogen (which, in turn, make the development of breast gland tissue more likely).

Higher levels of fat also leads to a reduction of testosterone and an increase in estrogen; an enzyme called aromatase converts testosterone into estrogen.

The bulk of this conversion happens in fat tissue (85% of it, in fact), and so the more fat tissue you have, the higher your estrogen levels will be.

Hypogonadism

Hypogonadism is a condition wherein the (male) subject suffers from a lack of androgens (male hormones).

This may be caused by damage to the testes (whether radiological, mechanical or pathological in nature) or it may be caused by damage to the pituitary gland or hypothalamus.

Tumors

Certain tumors can cause gynecomastia. Those typically responsible are tumors of the testes, pituitary gland, lungs and adrenal gland can cause an excess of estrogen and rapid-onset gynecomastia.

Prostate cancer is not directly responsible for gynecomastia, but the antiandrogen medications used in its treatment can be (as they suppress testosterone production).

Chronic Diseases

Disease of the liver and kidneys, as well as hyperthyroidism, can all wreak havoc on hormonal balance and lead to an increase in estrogen and a decrease in androgens.

Hyperthyroidism can also lead to an increase in androgens, which ironically results in a corresponding increase in estrogen (the excess androgens are converted by the body).

Reasons Unknown

And remember, many cases of gynecomastia though can be attributed to unknown reasons, and an underlying hormone imbalance cannot be identified.

Be sure to talk with your surgeon to understand if surgery is right for you.