Polycystic ovary syndrome (PCOS) is known as the most common endocrine disorder of women in reproductive ages, with the prevalence ranging from 6 to 15%. The most common clinical manifestations of this syndrome include irregular menstrual cycles, infertility, acne, hair loss with the male pattern, insulin resistance and obesity. According to Rotterdam criteria, PCOS diagnosis depends on the identification of at least two of the following three features: oligo-anovulation, hyperandrogenism and polycystic ovaries in ultrasound. Patients with PCOS are at increased risk for the development of metabolic syndrome, type II diabetes mellitus, and cardiovascular diseases. Along with specific medications, lifestyle modifications, such as dietary pattern, exercise, and behavioral therapies, are the first line of treatment for PCOS. Yet, attention to medicinal herbs has recently expanded as an alternative treatment or diseases control.
Flaxseed (Linum usitatissimum) is a rich source of several biologically active compounds, including α-Linolenic acid, phytosterogenic lignans (seco-isolariciresinol, enterolactone, ecc.) and dietary fibers. Prior studies have indicated that high lignin foods increased testosterone exertion by binding it to enterohepatic circulation. Lignans could also reduce the bioavailability of free testosterone through increasing a blood globulin called SHBG. Flaxseeds help intestinal evacuation, reduce cholesterol absorption and improve plasma fat profile. For this reason a team from the Department of Nutrion of Jundishapur University in Ahvaz, Iran, has tested the idea that flaxseed supplementation could improve the metabolic and hormonal status in women with PCOS. The team performed a pilot clinical trial where participants were randomly allocated into two groups to take either 30 g/day brown milled flaxseed (n=24) together with Lifestyle Modification (LM) or LM alone (n=24) for 12 weeks.
The dose of 30 g/day for flaxseed powder was chosen based on the recommendations from three systematic reviews and meta-analyses, which suggested that 30 g/day flaxseed powder or greater doses were most effective in normalizing inflammatory biomarkers, lipid profiles, and body composition for up to 12 weeks. The present study results revealed no significant changes in testosterone and SHBG concentrations in the flaxseed group in comparison to the control group. Flaxseed supplementation for 12 weeks led to a significant reduction in body weight, waist circumference, and BMI in the women with PCOS. We showed that flaxseed powder consumption caused a significant improvement in the menstrual cycle regulation that was in line with previous findings. Most of the subjects in this trial had menstrual cycle disturbance. The present study findings indicated that daily flaxseed supplementation decreased leptin level and improved adiponectin level.
Scientists think that his beneficial effect might be due to the higher amounts of lignan and fiber that can improve insulin sensitivity by reducing glucose uptake speed and insulin release. Furthermore, some researchers have suggested that omega-3 fatty acids in flaxseed could increase adiponectin level, which has antiatherosclerotic, antidiabetic, and anti-inflammatory properties by improving insulin sensitivity. Omega-3 fatty acids in flaxseed can change the transcription of hepatic genes involved in lipid metabolism, especially receptors PPAR-α and SREBP1c. In the current study, flaxseed intake was associated with lower levels of reactive C-protein (CRP), a well-known inflammatory biomarker. This finding was consistent with those of the previous studies. Seco-isolariciresinol is an active compound in flaxseed, specifically a lignan, which has anti-inflammatory effects.
Therefore, along with omega-3 acids and some polyphenols, this compound may exert the anti-inflammatory effect seen in PCOS women. The researchers have not excluded the hypothesis that flaxseed fibers, once fermented in the gut, may originate beneficial compound from microbiota (especially the short-chain fatty acids like butyrate), though no dedicated experiments were performed on this topic. In conclusion, controlled flaxseed doses may represent a safe and complementary help for women with polycystic ovary, that may improve their metabolic and lipid profile through a partial control on the inflammatory component.
- Edited by Dr. Gianfrancesco Cormaci, PhD; specialist in Clinical Biochemistry.
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