Gynaecomastia questions, answered

Gynaecomastia is breast gland tissue growing in a man or boy. It shows as a firm, rubbery disc under the nipple, on one or both sides, and it is often tender at first. It is not the same as chest fat, and it is very common: about half of teenage boys get some during puberty.

Not always. "Man boobs" is used for both true gynaecomastia (gland) and chest fat. Gland feels like a firm disc behind the nipple; fat is soft all over. Many men have a mix of the two.

Often, yes. In teenagers it usually settles within six months to two years. In adults it often settles once the cause is dealt with, such as a medicine, steroids or weight. Tissue that has been there for more than a year tends to turn fibrous and stays.

Exercise burns fat, so it helps when the chest is mostly fat. It can't shrink gland tissue, and chest workouts build muscle underneath, which can push the disc forward. If the firm disc is still there after you're lean, exercise won't move it.

When it's new and you're an adult, when it's on one side, when it's painful, or when it's growing. See a GP soon for a hard or fixed lump, nipple discharge or blood, a pulled-in nipple, skin changes or a lump in the armpit.

For long-standing gland tissue in an adult whose weight is steady and whose GP has checked for a cause, yes, surgery is the treatment that removes it. In Ireland it costs €3,000 to €6,900 privately, our price guide. It isn't for teenagers who are still growing.

Nobody, unless you choose to send it. If you do, one Irish clinic contacts you to arrange a consultation with a surgeon. Nothing is booked until you say yes.

Yes. It often starts on one side and sometimes stays that way. A one-sided change in an adult should still be checked by a GP, so the doctor can feel it and rule out other causes. Our one-sided guide explains what they look for.

Not directly. Stress can change weight, sleep, drinking and medicines, and those can play a part. There's no good evidence that stress on its own grows breast tissue.

Very likely, if there's a firm disc behind them. Puffy nipples on a lean chest are one of the most common shapes of gynaecomastia, often after steroids or from puberty.

Private clinics in Ireland usually see you without one, but many surgeons like a GP letter, and some want your test results first. A GP check first also rules out a cause that surgery wouldn't fix.

Yes. It often starts on one side or grows unevenly. It usually evens out or goes as puberty goes on.

Recent tissue often goes down over a few months once testosterone recovers. Tissue that has been there for a year or more usually stays.

Usually not. Most are gynaecomastia. A GP should still feel it, because the rare exceptions are found that way.

Sometimes. A GP can check your testosterone with a morning blood test. Low testosterone has other signs too, such as low energy, low sex drive and poorer sleep.

Yes, often, when it's recent and the cause is dealt with. Long-standing, fibrous tissue doesn't.

No exercise targets the chest. Whole-body strength training plus a steady calorie deficit shrinks chest fat; it won't shrink gland.

Yes, for daytime, if it fits properly and doesn't leave marks or make breathing hard. Take it off to sleep.

Health insurance plans normally exclude cosmetic surgery, except to correct disfigurement from a condition you were born with, an accident or a disease. Whether a male breast reduction counts depends on your plan and your surgeon's report, so ask your insurer in writing before anything is booked.