Gynecomastia is the growth of breast tissue in males causing enlarge in the size of breasts. It can be on either breasts or both. It is caused due to an enlarge in estrogen levels decrease in testosterone levels in the male body. It might happen in the primary couple of weeks after birth, in the pubescent stages of a boy’s life or in old age. Or it might be caused as a side effect from other severe illnesses such as hyperthyroidism, kidney failure and liver cirrhosis.