Overdevelopment of male breasts is a condition known as gynecomastia. Gynecomastia can affect men of all ages and most commonly is the result of genetics, hormonal changes, certain drugs or medications, and weight gain. Gynecomastia affects approximately one out of two men at some time in their lives. This condition is characterized by excess breast fat and glandular tissue and can be present in one (unilateral) or both (bilateral) breasts. Gynecomastia can cause emotional di