What Are the Causes of Male Breast Enlargement?

Overview

Traditionally speaking, males don't have significantly large breasts. Breast enlargement is considered to be a secondary sexual characteristic of females. Consequently, male breast enlargement (also known as gynecomastia) usually only happens if something in the body becomes unbalanced, such as unusually high levels of estrogen.

Identification

Male breast enlargement is also known as gynecomastia. It usually begins with a small lump under the nipple that gradually gets larger. This can cause men's breasts to get bigger, often irregularly.

Puberty

The most common cause of gynecomastia is puberty. During puberty, a male's production of hormones rises dramatically. Normally, the main increase is found in the levels of androgens, which are hormones (such as testosterone) that promote male sexual characteristics. However, in some males the levels of estrogen rise as well. If these become too high, it can cause development of the breast tissue in men, leading to gynecomastia.

Exogneous Hormones

Another reason male breast enlargement can happen is the result of exposure to synthetic hormones. Some men, for example, take anabolic steroids, which increase the body's levels of androgens. However, the body may compensate for this unilateral hormonal surge by making more estrogen, leading to breast tissue enlargement. Exposure (whether accidental or intentional) to estrogen also causes breast tissue to enlarge.

Other Causes

Other causes include liver and kidney disease, as problems with both of these organs can cause fluid retention and swelling of the breast tissue. Marijuana use can cause gynecomastia, as well as some medications. Finally, low levels of testosterone in the body can also lead to increased estrogen production, which leads to gynecomastia.

Rare Causes

There are some rare causes of male breast enlargement. These include underlying genetic causes (which can make male breast enlargement difficult to diagnose), problems with the thyroid, and the development of a tumor. The latter is especially a concern for doctors because these tumors can be a symptom of breast cancer--which, although rare, can develop in men.