Male hypogonadism associated with obesity by yet not fully understood mechanisms promote fat depositions and on contrary obesity induces decrease of androgen production. It is necessary to diagnose hypogonadism correctly and to treat it. The definition of hypogonadism is based on subnormal levels of circulating testosterone and on the occurrence of symptoms, which, however, are not much specific. As obesity decreases substantially the concentrations of sex hormone binding globulin SHBG it is recommended in these men to check not only the level of total testosterone but also the concentration of free testosterone or the value of the index of free androgens. Proven hypogonadism in obese men should be treated as well as by testosterone substitution as the body mass reduction. The most effective treatment in this respect is considered bariatric surgery.
Keywords: SHBG; male hypogonadism; obesity; testosterone..