How Does a High-Protein Diet Affect Insulin Sensitivity?
HealthDay News — Postmenopausal obese women who lose weight eating a high-protein diet may not experience any improvements in insulin sensitivity, according to a study published in the October 11 issue of Cell Reports.
Bettina Mittendorfer, PhD, a professor of medicine at the Washington University School of Medicine in St. Louis, and colleagues tracked outcomes over seven months for 34 obese women aged 50 to 65, none of whom had diabetes at the study's outset. The women were divided into three groups: a no-dieting group where women simply maintained their weight; a dieting group that ate the recommended daily level of protein; and a dieting group that followed a high-protein regimen.
The researchers found that at the end of the study period, women who ate a high-protein diet did not show improvement in insulin sensitivity. The women who dieted but ate the standard amount of protein had a 25 to 30% improvement in their insulin sensitivity. The researchers also found that consuming high levels of protein offered little benefit in terms of preserving muscle while dieting.
"When you lose weight, about two-thirds of it tends to be fat tissue, and the other third is lean tissue," Mittendorfer said in a university news release. "The women who ate more protein did tend to lose a little bit less lean tissue, but the total difference was only about a pound. We question whether there's a significant clinical benefit to such a small difference."