OBJECTIVE: The metabolic syndrome (MS) is associated with low serum testosterone levels. Conversely, low testosterone levels induce MS. These operational mechanisms reinforce one another and induce a vicious cycle. This is a report on a morbid obesity 42 year-old man with the MS and serum testosterone of 5.0 nmol/L (N: 12.0-33.0), who was resistant to treatment with diet and exercise. He was treated with testosterone undecanoate for 16 months. METHODS: Anthropological and laboratory variables were measured before and during testosterone […]