Gynecomastia is a swelling of the breast tissue in boys or men, caused by an imbalance of the hormones estrogen and
testosterone. Gynecomastia can affect one or both breasts, sometimes unevenly. signs and symptoms usually include swollen breast gland tissue and breast tenderness. In most cases if the causative factor is removed it will regress over time. I would advise you to Exercise regularly, eat a well balanced diet, loose weight to a healthy weigh according to your BMI, avoid habits such as smoking and drinking(which could also lead to development of gynecomastia). There are also surgical options of treatment.