Effects of protein versus simple sugar intake on weight loss in polycystic ovary syndrome (according to the National Institutes of Health criteria).

Objective: To compare the effects of protein vs. simple sugars on weight loss, body composition, and metabolic and endocrine parameters in polycystic ovary syndrome (PCOS).

Design: A 2-month, free-living, randomized, single-blinded study.

Setting: University PCOS clinic.

Patient(s): Thirty-three patients with PCOS.

Intervention(s): To achieve a final energy reduction of 450 kcal/day, first the daily energy intake was reduced by 700 kcal; then a 240-kcal supplement containing either whey protein or simple sugars was added.

Main Outcome Measure(s): Changes in weight, fat mass, fasting glucose and insulin, plasma lipoproteins, and sex steroids.

Result(s): Twenty-four subjects (13 in the simple sugars group and 11 in the protein group) completed the study. The protein group lost more weight (-3.3 +/- 0.8 kg vs. -1.1 +/- 0.6 kg) and more fat mass (-3.1 +/- 0.9 kg vs. -0.5 +/- 0.6 kg) and had larger decreases in serum cholesterol (-33.0 +/- 8.4 mg/dL vs. -2.3 +/- 6.8 mg/dL), high-density lipoprotein cholesterol (-4.5 +/- 1.3 mg/dL vs. -0.4 +/- 1.3 mg/dL), and apoprotein B (-20 +/- 5 mg/dL vs. 3 +/- 5 mg/dL).

Conclusion(s): In patients with PCOS, a hypocaloric diet supplemented with protein reduced body weight, fat mass, serum cholesterol, and apoprotein B more than the diet supplemented with simple sugars.