Effects of ketogenic diet on weight loss parameters among obese or overweight patients with polycystic ovary syndrome: a systematic review and meta-analysis of randomized controlled trails.

None

• PCOS can make WL more challenging due to its effects on hormonal and metabolic imbalances.

• A KD, which is characterised by low-carbohydrate and high-fat intake, may be a potential dietary regime for promoting reductions in body weight, WC, BMI and FM in overweight or obese women with PCOS.

• Short-term dietary interventions can lead to observable improvements in body measurements for overweight or obese women with PCOS.

Introduction

Polycystic ovary syndrome (PCOS) is a hormonal and metabolic condition in which patients often experience insulin resistance, dyslipidaemia and difficulty with weight management. This study aimed to evaluate the efficacy of ketogenic diets (KDs) on weight loss (WL) parameters, including weight, waist circumference (WC), body mass index (BMI), and fat mass (FM), in overweight or obese women with PCOS.

Methods

This was a systematic review and meta-analysis of eleven articles (including twelve trials) involving a total of 426 women with PCOS. Among the included articles, three were randomised, double-blind, placebo-controlled trials comparing ketogenic diets with alternative dietary interventions (such as hypocaloric or balanced diets). Whereas the remaining eight were before–after studies where participants acted as their own controls. The duration of the intervention across the included studies varied from 6 to 24 weeks.

Results

The pooled results of the meta-analysis showed that patients with PCOS following a KD, experienced statistically significant reductions in:

• weight (WMD = −9.13 kg; 95% CI, −11.88 to −6.39; P < 0.01; I 2 : 87.23%)

• BMI (WMD = −2.93 kg/m2; 95% CI, −3.65 to −2.21; P < 0.01; I 2: 78.81%)

• WC (WMD = −7.62 cm; 95% CI, −10.73 to −4.50; P < 0.01; I 2: 89.17%)

• FM (WMD = −6.62 kg; 95% CI, −8.44 to −4.80; P < 0.01; I 2: 53.92%)

Conclusion

The authors concluded that based on KDs potential in decreasing body weight, BMI, WC, and FM in obese or overweight women with PCOS, dietary modifications can play a significant role in supporting weight management in this population.

• A nutrient-dense low-calorie diet may be an effective nutritional strategy for managing PCOS.

• KDs may be part of a dietary intervention to support WL, BMI reduction, and improved body composition in overweight or obese women with PCOS.

• KDs with very low-carbohydrate intake (<20 g/day) may help improve insulin sensitivity and metabolic outcomes in overweight or obese women with PCOS.

• Personalised protein intake as part of a KD may help maintain lean muscle mass during WL interventions.

• Long-term follow-up studies are needed to determine whether the benefits of KDs in women afflicted with PCOS can be maintained with less restrictive and more sustainable dietary patterns.

• Future studies should assess the durability of WL and metabolic improvements over a long period of time compared to short-term outcomes reported in current trials.

• Additional larger and well-designed randomised controlled trials are needed to strengthen the current evidence and help determine which dietary patterns are more effective.