Not Just Fat: The Truth You May Not Know About Men's Breasts
Men experience changes in their breasts just like women do. Sometimes it is due to fat deposits or the growth of breast tissue. But what does it mean when a man's breasts are larger than normal?
For some men, the breasts are as large as those of women, and the main cause is adiposity. In medical terms, this refers to the growth of breast tissue. In many cases, it is the growth of both fat and tissue at the same time.
Gynecomastia is more common than many people think. Research shows that asymptomatic gynecomastia—growth that doesn't cause pain or discomfort—occurs in 30% to 50% of healthy men. That means nearly half of all men may experience some degree of gynecomastia at some point in their lives, even if they never notice it.
Structure and function of the chest
In both men and women, the breasts lie on top of the pectoral muscles and consist of two main components: fat and glandular tissue.
Fat gives the breast its size and shape; it is soft and can increase or decrease with weight changes. Glandular tissue—made up of milk ducts and supporting structures—responds to hormones. In women, estrogen stimulates tissue growth during puberty and pregnancy . In men, testosterone keeps the tissue small and undeveloped, but the structure remains intact: milk ducts, milk glands, and nipples.
This is why men can also develop breast conditions, such as gynecomastia or, in rare cases, cancer. Understanding this combination of fat and glandular tissue explains why " man boobs " can mean different things depending on which part is developing.
The fetus starts with a 'female blueprint.' Nipples form before the Y chromosome signals the body to develop male characteristics. By the time testosterone kicks in, nipples have formed—a harmless evolutionary sign that men and women share the breast structure, even though they are largely inactive in men.
It may sound crazy, but under certain conditions, men can produce milk. Men have the same basic breast structure as women, including milk ducts and cells capable of producing milk. However, these cells are often suppressed by testosterone and controlled by the body's overall hormonal balance. Additionally, men do not have the surge of prolactin that stimulates milk production in women.
Certain medications that increase prolactin levels, pituitary gland disorders, chronic liver disease, or hormone therapy for prostate cancer can sometimes activate these cells. The result is abnormal milk production. This is rare and usually harmless, but you should see your doctor if it happens, especially if the discharge is persistent or bloody.
Reasons why men have breasts like women
Fat is the most common reason why men notice fuller breasts. As men gain weight, fat can accumulate in their breasts, as well as in their abdomen or hips. This condition, known as pseudogynecomastia, is extremely common today.
Breast fat is soft and spread out, not hard or tender. This condition is not medically dangerous and usually improves with weight loss, exercise, and healthy lifestyle changes.
Big Breasted Men: The Real Development of Breast Tissue
Gynecomastia — the growth of glandular breast tissue below the nipple and areola, the darker skin surrounding the nipple — is not caused by fat. The tissue is usually firmer and sometimes soft, and lies just below the nipple.
This development occurs when the balance between testosterone and estrogen is altered. During puberty, up to two-thirds of males experience some degree of gynecomastia. This condition is normal and usually temporary. Since it usually resolves on its own once hormones stabilize, treatment is rarely needed.
However, as men age, similar hormonal changes can occur again. In older men, due to the natural decline in testosterone, breasts become larger, often due to weight gain or medications that alter hormone levels.
Other causes of excessive breast tissue growth in men
Hormones aren't the only culprit. Medications, stimulants, and health conditions can all contribute.
Finasteride, prescribed for hair loss or prostate enlargement, and bicalutamide, used to treat prostate cancer, can alter the effects of testosterone and allow breast tissue to grow. In some cases, stopping the drugs will reverse the growth. But if the tissue has been there long enough, it may not shrink completely.
Alcohol and marijuana can also affect hormones, especially when used heavily or regularly. Anabolic steroids – popular in bodybuilding – are another factor that causes breast changes and growth.
Thyroid, liver, or kidney disease can also disrupt hormones in ways that promote breast tissue growth. In those cases, breast changes may be a warning sign of a more serious health problem.