What do you mean by man boobs?
They refer to the abnormal growth of male breasts. Its medical term is gynecomastia. The male breasts usually enlarged during puberty that basically disappears as boys grow up. Man boobs are common to overweight men.
The effective way to lose them is to exercise and develop muscles in your chest area and do some fat burning workouts. The muscles reduce the chances of fat build up in your chest and heightened the rate of fat burned in the breast area. If you want to lose them, find a lot of guaranteed ways on how to get rid of man boobs in the Internet.