The Effect of Garlic (Allium Sativum) on Polycystic Ovary Syndrome Related Hormones and Glycemic Parameters: A Randomized, Double‑Blinded Clinical Trial

Roya Zadhoush, Amirmansour Alavi‑Naeini, Awat Feizi, Elham Naghshineh, Mohammad Reza Ghazvini


Background: The purpose of the present study was to investigate the effect of garlic supplementation on androgen levels and glycemic‑related markers in patients with PCOS. Methods: In these 8 weeks of randomized double‑blinded control trial, 80 women were randomly assigned into two groups in which patients were asked to intake either 800 mg/day garlic or an identical placebo. A blood sample was obtained pre‑ and post‑trial to assess androgens and glycemic‑related parapets. A 3‑days‑ food record and a short form of international physical activity questionnaires (IPAQ) were also evaluated at the beginning and end of the trial. Results: All participants completed the trial. Garlic supplementation resulted in significant reduction in fasting plasma glucose (‑3.22 ± 7.41 vs. 0.72 ± 5.37; P = 0.008) and homeostatic model assessment for insulin resistance (HOMA‑IR) (‑0.29 ± 1.45 vs. 0.28 ± 1.20; P = 0.02). In addition, a trend to a significant improvement was detected in free androgen index (FAI) (P = 0.09), insulin levels (P = 0.07), and quantitative insulin sensitivity check index (QUICKI) (P = 0.06). However, no significant difference was found in testosterone and sex hormone‑binding globulin (SHBG) (P > 0.05). Conclusions: Present study indicates that garlic supplementation could be beneficial for FPG and insulin resistance improvement. However, garlic supplementation does not show remarkable efficacy on androgens. Further studies are warranted to confirm the results.


Garlic; insulin resistance; polycystic ovary syndrome; testosterone

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