Evaluation of Effects of a High-Protein Hypocaloric Diet on Body Composition and Cardio-Metabolic Factors in Women with Polycystic Ovary Syndrome and Overweight or Obesity.

Abstract

Background: The optimal composition of a hypocaloric diet for women with polycystic ovary syndrome (PCOS) remains uncertain. The aim of this study was to evaluate and compare the impacts of a hypocaloric high-protein diet (HPD) versus an isocaloric conventional calorie-restricted diet (CRD) with normal protein intake on the body composition and biochemical profiles of women diagnosed with PCOS combined with overweight or obesity.

Methods: This was a dietary intervention study evaluating the effects of two types of diets on women with PCOS who initiated weight loss independently at the Clinical Nutrition Clinic of Peking Union Medical College Hospital from March 2023 to March 2024 was carried out. Specifically, the records of 72 women with PCOS who were overweight or obese and underwent a 3-month weight management program were examined in a retrospective manner. The hypocaloric dietary intervention was adopted to achieve weight reduction, with either HPD or CRD. Body composition, serum lipids, glucose, insulin, and total testosterone (TT) were evaluated at baseline and post-intervention, and the differences were compared between and within groups.

Results: Both groups achieved significant weight loss, with the HPD group losing an average of -8.9 ± 4.6 kg and the CRD group losing -10.0 ± 9.4 kg, without a significant difference between them (P > 0.05). However, the HPD was superior in preserving fat-free mass (FFM) and fat-free mass index (FFMI), with losses of -1.5 ± 1.6 kg and -0.7 ± 1.1 kg/m², respectively, compared to the CRD group's losses of -4.4 ± 4.2 kg and -2.1 ± 1.9 kg/m² (P < 0.01). Additionally, the HPD group showed a more significant reduction in body fat percentage (-5.3 ± 3.3% vs -3.2 ± 4.5%, P < 0.05). Biochemical indicators were comparable in both groups.

Conclusion: Compared to an isocaloric standard-protein CRD, the dietary intervention with a HPD appears to be more helpful in preserving FFM in women with PCOS during a short-term weight loss program. Further well-designed trials are needed to verify our findings.