Overview | Causes | Treatment | Prevention | Key Takeaways | FAQs

Medically Reviewed April 2023, by Claire Clarke - Head of Surgical Services for The Harley Medical Group
What are man boobs?
'Man boobs' or gynaecomastia is a condition that causes male breasts to grow and become larger than normal. Symptoms include swollen breast tissue and breast tenderness.
Enlarged breast tissue in men and boys is a common occurrence, especially among certain groups. Up to 60% of males struggle with man boobs, most of whom are infants, teenagers, or men over the age of 50.
Although gynaecomastia may be triggered by several medical conditions, in most cases, enlarged breast tissue is a consequence of excess fat accumulated on the chest.
What causes man boobs?
Gynaecomastia is caused by a drop in testosterone levels. Testosterone is a hormone associated with the male gender characteristics and it prevents breast tissue from expanding.
The decrease in testosterone levels may be triggered by a range of conditions that block the effects of testosterone, weaken it, or increase oestrogen levels (hormone associated with female characteristics).
Males who are going through hormonal fluctuations can also develop enlarged breasts.
Some of the main factors causing gynaecomastia are:
- hormonal fluctuations (e.g. in infancy - from mother's oestrogen, during puberty, between the ages of 50 and 69)
- certain medications that block the effects of testosterone
- excessive alcohol consumption
- using certain drugs
- other underlying conditions (e.g. overactive thyroid, obesity, certain types of tumours, kidney and liver disease, hypogonadism etc.)
Drugs causing gynaecomastia
Certain medications or treatments may trigger gynaecomastia.
- anti-ulcer medications
- psychiatric medications
- certain antibiotics
- AIDS medications
- cancer treatment
- supplements with phytoestrogens

How to get rid of man boobs
Gynaecomastia can be treated through lifestyle changes, medical treatment or a combination of both.
Losing body fat through diet and exercise can reduce the appearance of man boobs, however, some of the breast tissue will not disappear by simply losing the fat - which may warrant undergoing cosmetic surgery.
It's important to know that you cannot lose fat in one particular area of the body, but you can work to strengthen certain muscles to balance out the overall look of your chest. Cosmetic surgery is often a solution when dietary changes or medication have failed to work.
Male chest reduction surgery - key facts
- Aims to remove fat in the breast, which is often done through liposuction.
- The surgeon may have to remove breast excess tissue by making a small incision around the lower half of the nipple area alongside carrying out liposuction. In certain cases, a combination of both works best.
- The operation takes up to 2 hours to complete and has a short recovery time. It can be carried out on an outpatient basis, or via an overnight stay.
Diet and exercise can reduce the appearance of man boobs when male chest enlargement is caused by excess fat deposits resulting from weight gain.
- Diet: small, but sustainable dietary changes to boost gradual weight loss will support overall health. Raw foods, vegetables and high-fibre meals will help reduce caloric intake whilst preserving energy levels.
- Exercise: workouts that reduce overall weight and target the loss of chest fat will help you tone your body. High-intensity activities like cycling, jogging or swimming are great for maintaining heart health and losing weight. Targeted chest workouts can be carried out at home, or in a gym.
If you notice a one-sided lump on any one of your breasts, seek immediate medical attention from your GP. They will refer you to a specialist who can assess your condition and request tests to exclude cancer or other serious illness.

When to see a doctor
You should seek medical attention immediately if:
- you experience swelling
- the chest area is painful
- there is discharge coming out of the nipples
- you notice a one-sided lump on one of your breasts has suddenly appeared
If a medical condition is triggering gynaecomastia, see your doctor to get the correct medication prescribed.
Alternatively, if man boobs are causing you psychological distress, a GP may refer you to an endocrinologist or cosmetic surgeon to address the issue.
Speak to a patient advisor
Prevention and lifestyle tips
While you cannot do anything to prevent natural hormonal changes, there are a few ways to ensure you don't develop gynaecomastia for other reasons.
- Exercise regularly and introduce strength training into your workout routines
- Maintain a healthy, nutritious diet
- Avoid medicines or drugs that are known to cause gynaecomastia
Summary
Gynaecomastia is a very common disease that causes enlarged breast tissue in males (man boobs). It can develop as a side effect to certain medications, hormonal fluctuations or another underlying condition.
In certain cases, gynaecomastia can be resolved with dietary changes and exercise. Sometimes, your doctor may recommend cosmetic surgery to remove the excess breast tissue.