Influence of sex on total and regional fat loss in overweight and obese men and women

Abstract

To determine the influence of sex on the association between reductions in body weight (BW) and waist circumference (WC) with reductions in total (TAT), subcutaneous (SAT) and visceral adipose tissue (VAT) in response to lifestyle-based interventions. Changes in TAT, SAT and VAT were assessed using magnetic resonance imaging in 81 men and 72 women who had participated in various diet and/or exercise interventions at Queen's University, Ontario, Canada. Reductions in BW and WC were significantly (P<0.001) correlated with TAT, SAT and VAT loss in men and women. For a given weight loss, men had a significantly greater decrease in WC than women, and the sex difference in WC reduction increased with increasing weight loss (P<0.05). Similarly, for a given reduction in BW or WC, men have significantly greater reductions in VAT, but smaller reductions in total and lower body SAT than women, differences that progressively increased in magnitude with the increasing BW or WC loss (P<0.05). Accordingly, there were no sex differences in the TAT reduction for a given BW or WC reduction (P>0.05). Reductions in BW and WC were both independent predictors of VAT loss. These observations suggest that for a given reduction in BW or WC, men lose more VAT and less SAT than women; however, the TAT loss observed for a given reduction in BW or WC in men and women is not different.