What Is Gynecomastia? Causes, Symptoms, and When to Seek Treatment

Gynecomastia is the enlargement of glandular breast tissue in men, giving the chest a fuller, sometimes tender appearance. It's a common condition — affecting a significant proportion of men at some point in their lives — and it's not the same thing as simply carrying extra fat on the chest.

Gynecomastia vs. Chest Fat

This distinction matters because it affects what actually works to treat it. Chest fat (sometimes called "pseudogynecomastia") is fatty tissue that can shrink with weight loss and exercise, much like fat anywhere else on the body. True gynecomastia involves enlarged glandular tissue itself, which does not respond to diet or exercise in the same way — no amount of chest workouts will shrink glandular tissue that has already enlarged. Many men have some combination of both, which is one reason a proper in-person assessment matters more than guessing from a mirror.

Common Causes

• Hormonal shifts during puberty, which often resolve on their own over one to two years
• Natural age-related hormonal changes
• Certain medications and, less commonly, underlying medical conditions
• Anabolic steroid or certain supplement use
• In many cases, no clear identifiable cause at all

Symptoms to Watch For

Gynecomastia typically presents as a firm or rubbery mass of tissue beneath the nipple, sometimes with tenderness, on one or both sides. It's worth having any new breast enlargement, especially if it's one-sided, hard, or associated with skin changes or discharge, properly evaluated — a clinical assessment (occasionally with imaging or blood tests) can rule out other causes before treatment is discussed.

When Treatment Becomes an Option

Many cases of adolescent gynecomastia resolve without any treatment. For persistent gynecomastia that hasn't responded to addressing any underlying cause, or that is causing ongoing self-consciousness or discomfort, surgical correction is the definitive treatment — see the gynecomastia surgery procedure page for how it's approached.