Visceral fat loss induced by a low-calorie diet: a direct comparison between women and men

No studies have assessed if changes in visceral adipose tissue (VAT) during weight loss differ between women and men with comparable amounts of VAT at baseline. The aim of this study was to assess if changes in VAT induced by a low-calorie diet (LCD) differ between women and men. In this post hoc analysis of an existing database, abdominal adipose tissue was evaluated before and after an 8-week LCD (800-1000 kcal/day) by a single-slice magnetic resonance scan performed at the abdominal level. Body composition was measured by dual X-ray energy absorptiometry. Data from 111 obese subjects (85 women and 26 men) were available. Relative changes in VAT were found to be more pronounced in men [mean (95% CI): -32.6% (-38.7 to -26.6)] than in women [-21.9% (-25.0 to -18.8)] (p = 0.003) after correction for relative changes in fat mass (FM). When analysing only the data from a subgroup of 23 women and 23 men who were matched for similar visceral to abdominal subcutaneous fat ratio at baseline, these differences could not be observed anymore: the change in VAT was -33.7% (-38.7 to -28.7) in men and -26.8% (-31.8 to -21.8) in women (p = 0.07). This study suggests that relative changes in VAT during a LCD may be greater in men than in women even after taking relative changes in FM into account. However, these differences disappear when properly matching the subjects for baseline amounts of VAT.