Sex- and menopause-associated changes in body-fat distribution

We investigated sex- and menopause-related differences in body composition and regional fat distribution, using dual-energy X-ray absorptiometry (DEXA) in nonobese healthy volunteers. Men (n = 103) had a 50% greater lean tissue mass (P less than 0.001) but a 13% lower fat mass (P less than 0.001) than the women (n = 131). Postmenopausal (n = 70) women had a 20% greater fat mass (P less than 0.001) than premenopausal (n = 61) women. The proportion of android (upper body) fat was greatest in men (48.6%, P less than 0.001) but was significantly lower in premenopausal (38.3%) than in postmenopausal (42.1%) women (P less than 0.001). The reverse was found for gynoid (lower body) fat (P less than 0.001). DEXA measurements thus clearly demonstrated that sex differences in total fat mass were opposite those of android fat, and that marked menopausal changes in fat mass and its distribution existed. Body mass indices did not demonstrate that men had less total fat than women whereas postmenopausal women had more total fat than did premenopausal women. Our findings suggest that DEXA measurements of fat distribution may be useful for studies related to obesity-associated disease risk.