Though this oddly named condition is rarely talked about, it’s actually quite common. Gynecomastia affects an estimated 40 to 60 percent of men. It may affect only one breast or both. Though certain drugs and medical problems have been linked with male breast overdevelopment, there is no known cause in the vast majority of cases. For men who feel self-conscious about their appearance, breast reduction surgery can help. The procedure removes fat and or glandular tissue from the breast, and in extreme cases removes excess skin, resulting in a chest that is flatter, firmer, and better contoured.