Objective: To correlate anthropometric, computed tomography and fat cell data from abdominal regions with the levels of serum insulin, C-peptide, leptin, tumor necrosis factor-alpha (TNF-a), testosterone, 17b-estradiol, androstenedione, dehydroepiandrosterone sulphate (DHEA-S) and sex hormone-binding globulin (SHBG). Design and methods: The sample consisted of 84 obese patients (29 men, 22 premenopausal women and 33 postmenopausal women) who had undergone abdominal surgery. Weight, height, percentage of body fat by skinfolds, waist, hip and thigh circumferences, sagittal and coronal diameters, visceral and subcutaneous area, serum hormones and fat cell data were studied. Results and conclusions: Premenopausal women showed the lowest values in most abdominal distribution parameters, although, depending on the waist circumference criteria at the umbilicus level perimeter (W1) or midway between lower rib margin and iliac crest perimeter (W2), the population was classi®ed differently, as gynoid or android. Although there were no differences in fat cell size between genders, gynoid women had smaller and more numerous fat cells than the android type. Perivisceral fat cell size was signi®cantly smaller than subcutaneous fat cell size. In women, central obesity was signi®cantly correlated with an increase in serum insulin, leptin, TNF-a, testosterone and androstenedione levels, and a decrease in 17b-estradiol and DHEA-S, while in men signi®cant correlations were positive with insulin and negative with testosterone and androstenedione. Fat cell size was positively correlated with serum levels of leptin, insulin, DHEA-S, androstenedione and inversely correlated with SHBG. These data indicate that hormones seem to interact not only with body fat distribution but also with fat cell size. This interaction differs between genders and between the different abdominal adipose tissue regions.