Effects of a Short-Term (4 Weeks) Protein-Sparing Modified Fast on Plasma Lipids and Lipoproteins in Obese Women

Abstract

The aim of this study was to evaluate the effects of a short-term (4 weeks) protein-sparing modified fast (PSMF) diet of 400 cal on plasma lipids and lipoproteins in a group (n = 51) of pre- and postmenopausal women with moderately severe obesity (body mass index greater than 30) as well as the eventual relations of plasma lipids to the type of fat distribution. Women with android-type obesity had higher plasma cholesterol, low-density lipoprotein cholesterol (LDL-C), apoprotein B (apoB) and glucose levels and lower high-density lipoprotein cholesterol (HDL-C) levels and HDL-C/LDL-C ratio than women with gynoid-type obesity. Besides waist-hip ratio (WHR), also age was an important determinant of HDL-C and HDL-C/LDL-C. PSMF for 4 weeks caused a 20% decrease in plasma cholesterol, LDL-C and apoB levels but also a decrease of HDL-C, apoA1 and apoA2. Nevertheless the HDL-C/LDL-C ratio increased, and, overall, PSMF resulted in less atherogenic profile of plasma lipids. Weight loss was independent of WHR but somewhat higher in premenopausal women (mean 10 kg) than in postmenopausal women (mean 8 kg), suggesting a more important energy deficit in pre- than in postmenopausal women. No correlation was observed between the importance of weight loss and the changes in plasma lipid levels: this indicates that the normalization of plasma lipids is the consequence of the diet itself and not secondary to weight loss.