Sex hormones and bariatric surgery in men.

The aim of this article is to review the available literature on the effect of weight loss after bariatric surgery on sex hormone levels and sexual quality of life in obese men, discuss the underlying physiology, and compare the effects of surgical and nonsurgical weight loss on sex hormone levels. Clinical trials investigating sex hormone levels in obese men after surgical and nonsurgical weight loss were identified in a Medline search. The results were synthesized, tabulated, and interpreted. Total testosterone and free testosterone are usually decreased in obese men, but were increased by both surgical and nonsurgical weight loss. The improvement in total testosterone after bariatric surgery was found to be greater than with nonsurgical weight loss in most studies. The changes were less clear on estradiol, gonadotropins, and adrenal androgens after both methods of weight loss and require further study. Improvement of sexual quality of life was more consistent with bariatric surgery. Thus, bariatric surgery is the most effective treatment of obesity-related male hypogonadism. This finding might motivate obese men with hypogonadism to opt for surgical weight loss.