Gynecomastia, the big breast problem in men, is the growth of the male breast similar to the female breast. The breast tissue consists of adipose tissue and mammary glands (parenchyma) in both men and women. Gynecomastia can only be due to an increase in the amount of fat, only the amount of parenchyma or the increase in both the amount of fat and the parenchyma. Which tissue reproduces can be determined by performing breast ultrasound. Breast enlargement in men is observed due to hormonal changes, adolescence, age, excessive alcohol consumption, liver disease and some medications.