High-protein intake eliminates the weight loss-induced improvement in insulin sensitivity

The purpose of this study was to conduct a randomized-controlled trial to evaluate the effect of a high-protein (HP) diet weight loss (WL) on changes in body composition, insulin sensitivity and skeletal muscle gene expression profile in postmenopausal women who were obese and randomized to one of three dietary intervention groups: 1) a weight maitenance group, 2) a weight loss group (normal protein intake, 0.8 g protein/kg body weight per day) and 3) a weight loss group (high protein intake, 1.2 g protein/kg body weight per day) and studies before and after they lost 10% of their body weight (WL groups) or a time-matched weight maintenacne period. We examined skeletal muscle samples obtained from two groups; 1) 9 subjects in a WL-HP group and 2) 6 subjects in a WL-NP group before and after 10% weight loss (i.e. the weight maitenance group was not included in the current microarray study).