OBJECTIVE: To pool evidence from clinical trials to study the effects of ketogenic diet on reproductive hormones (LH/FSH ratio, free testosterone, serum progesterone) and observe evidence of weight change.
METHODS: PubMed, ScienceDirect, Scopus, and Web of Science core collection were searched for clinical trials evaluating the effects of ketogenic diet in established PCOS women consistent with the Rotterdam classification. Single- or double-arm studies that included an outcome of interest were included. Two investigators worked independently to screen potential articles and a designated investigator extracted data on study characteristics and evaluated the outcomes. Data were pooled using a random-effects model. The quality of selected studies was assessed using the Cochrane Risk of Bias Tool.
RESULTS: Following ≥45 days of intervention with ketogenic diet among women with PCOS, significant improvement was observed in reproductive hormone levels, with reduced LH/FSH ratio (d -0.851; 95% CI -1.015, -0.686; P < .001), reduced serum free testosterone (d -0.223; 95% CI -0.328, -0.119; P < .001), and an increased in serum sex hormone binding globulin (SHBG) (d 9.086; 95% CI 3.379, 14.792; P = .002). Significant weight loss was unanimously observed in all included studies (d -11.56; 95% CI -14.97, -8.15; P < .001).
CONCLUSION: Short-term ketogenic diet potentially improved hormonal imbalances commonly associated with PCOS.