Soy for women with PCOS- it’s a good thing!
Reviewer: Tori Hudson, ND
Author: Jamilian M, Asemi A.
Reference: The effects of soy isoflavones on metabolic status of patients with polycystic ovarian syndrome. J Clinical Endocrinology and Metabolism. 2016, August, first published online.
Design: Women were randomly divided into two groups and received either soy isoflavone supplement (n=35) or placebo (n=35) for 12 weeks. Participants in the treatment group received 50 mg/day soy isoflavones containing 37.5 mg genistein, 10 mg daidzein, and 2.5 mg glycitein. Women were instructed not to change their usual physical activity level and not to take any nutritional supplements during the 12 weeks. Women completed a 3 day food record and three physical activity records at the study baseline, and weeks 3, 6, 9 and at the end of the trial. Macro and micronutrient intakes were analyzed by nutrition software.
Participants: This study included 70 women who had polycystic ovarian syndrome (PCOS) in Arak, Iran, ages 18-40 years. Women had to meet the Rotterdam criteria for PCOS, which was having two of the following criteria: 1) oligo and/or anovulation (defined as having a menses of > 35 days or < 8 spontaneous hemorrhagic episodes per year 2) clinical and/or biochemical signs of hyperandrogenism and 3) polycystic ovaries (12 or more follicles in each ovary measuring 2-9 mm in diameter, and/or increased ovarian volume > 10 mL3 . Women were excluded if they were pregnant, had elevated prolactin levels, thyroid disorder, diabetes, pre-diabetes or gastrointestinal problems.
Primary outcome: Markers of insulin resistance and androgens were considered the primary outcome. Lipid profiles and biomarkers of inflammation and oxidative stress were the secondary outcomes.
Key findings: After 12 weeks, alopecia decreased in the soy isoflavone group compared with the placebo group although acne was unchanged. After 12 weeks, the soy group had significantly decreased serum levels of insulin (-1.2 vs + 2.8), and HOMA-IR (-0.3 vs + 0.6) and HOMA-B ( -4.4 vs + 10.7) and increased QUICKI (0.0009 vs -0.01) . Supplementation with soy isoflavones also resulted in significant reductions in serum testosterone (-0.2 vs + 0.1), free androgen index ( -).03 vs + 0.02 ), decreased triglycerides (-13.3 vs + 10.3) and decreased VLDL-cholesterol (-2.7 vs + 2.0) compared to the placebo group. There were no significant effects of soy isoflavone intake on inflammatory and oxidative stress markers.
Practice Implications: Polycystic ovarian syndrome (PCOS) is a common endocrine problem that is diagnosed in reproductive aged women. It’s complex and involves multiple body systems but is associated with hyperinsulinemia, impaired glucose metabolism, hyperandrogenism and dyslipidemia. It is estimated that 5-6 million women in the United States have PCOS. The manifestations of PCOS can include irregular/infrequent menses or no menses at all, infertility, polycystic ovaries, abnormal hair growth (hirsutism), hair thinning, acne, weight gain and in time, an increased risk for type 2 diabetes, cardiovascular disease and endometrial cancer.
PCOS is a strong area for natural medicine that includes published research in nutrition, exercise, N-acetyl cysteine, myo-inositol, d-chiro-inositol, cinnamon, spearmint, licorice, fish oils and more., Daily soy intake, whether a soy isoflavone supplement, or possibly a soy food with 50 mg soy isoflavones should be added to a comprehensive treatment strategy.
 Muscoquiri, G. et al. Current Insights about Inositol Isoforms, Mediterranean and Ketogenic Diets for Polycystic Ovary Syndrome: From Bench to Beside. Curr Pharm Des. 2016 Jul 20. [Epub ahead of print].
 Arentz, S. et al. Herbal medicine for the management of polycystic ovary syndrome (PCOS) and associated oligo/amenorrhoea and hyperandrogenism; a review of the laboratory evidence for effects with corroborative clinical findings. BMC Complement Altern Med. 2014 Dec 18;14:511.