To examine the effects of alternate-day fasting on glucose metabolism, eight healthy men were maintained on a 20h modified alternate-day fast for two weeks. Despite unaltered body weight and habitual physical activity, insulin dependent glucose uptake increased, and increased adiponectin levels were observed (65). In another trial, the insulin sensitizing effect of true alternate-day fasting was observed through reduced insulin response to a standardized meal in men, but not women – suggesting a potential sex difference in the effect of alternate-day fasting on glucose metabolism (66). Although not demonstrated in all human studies (68,69), these results indicate that alternate-day fasting might mimic the insulin sensitizing effects observed in rodents on alternate-day fasting diet, and that the effect might be due to increased adiponectin levels.