Hormones and diet: low insulin-like growth factor-I but normal bioavailable androgens in vegan men

Mean serum insulin-like growth factor-I was 9% lower in 233 vegan men than in 226 meat-eaters and 237 vegetarians(P = 0.002). Vegans had higher testos terone levels than vegetarians and meat-eaters, but this was offset by high er sex hormone binding globulin, and there were no differences between diet groups in free testosterone, androstanediol glucuronide or luteinizing hor mone. (C) 2000 Cancer Research Campaign.