Study under review: Effects of Dietary Glycemic Index and Glycemic Load on Cardiometabolic and Reproductive Profiles in Women with Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis of Randomized Controlled Trials
Polycystic ovary syndrome (PCOS) is an endocrine and reproductive disorder characterized by an excess of hormones that regulate male characteristics (androgens) and ovulatory dysfunction. It affects about 6–20% of pre-menopausal women (depending on how it’s defined; see the sidebar below for more info on the definition of PCOS) and is associated with insulin resistance, dyslipidemia, and visceral adiposity (fat that surrounds vital organs like the liver and intestines). Some of the metabolic consequences of PCOS are depicted in Figure 1.
Adapted from: Escobar-Morreale. Nat Rev Endocrinol. 2018 May.
There is no universal treatment for PCOS. Since PCOS affects endocrine, reproductive, and, ultimately, metabolic health, treatment is individualized to the needs of the patient following first-line therapy that involves lifestyle, diet, and/or exercise modifications. However, beyond energy restriction, no consensus exists for specific PCOS dietary guidelines, as research is quite scarce for this common, yet often scientifically-neglected, condition.
Low glycemic index (LGI) diets focus on foods that have a minor effect on blood sugar levels, even though they may include a considerable amount of carbohydrates. Adherence to such diets can not only benefit blood sugar control, but also various cardiovascular and metabolic health measures in non-PCOS populations. The purported benefits of LGI diets overlap with PCOS pathophysiology. Some studies evaluating the relationship report promising results. However, conflicting results have also been reported, making it difficult to determine whether LGI diets would be a generally useful treatment option.
The authors of the study under review designed a systematic review and meta-analysis of randomized controlled trials (RCTs) to determine whether LGI diets might improve cardiometabolic and reproductive health measures in women with PCOS.
PCOS is an endocrine and reproductive disorder associated with metabolic dysregulation. LGI diets benefit glucoregulation and cardiometabolic health in non-PCOS populations, but results in PCOS populations report mixed results. The authors of the study under review designed a systematic review and meta-analysis to determine whether LGI diets might improve cardiometabolic and reproductive health measures in women with PCOS.
Other Articles in Issue #72 (October 2020)
NERD News: FDA allows certain cranberry products and dosages to claim that they reduce the frequency of recurrent UTIs in women.
The United States Food and Drug Administration is allowing qualified health claims for specific cranberry products. Emphasis on "qualified."
Chromium supplementation for glycemic control in type 2 diabetes
This meta-analysis suggests that chromium may help glycemic control, but the results weren't robust, leaving room for more high-quality evidence.
Alpha-lipoic acid for taming high triglycerides and boosting weight loss
The good news: R-ALA had a strong effect! The bad news: the effect was causing gastrointestinal problems.
Deep Dive: Low carb diets for type 2 diabetes: beneficial but difficult to maintain
Low carb diets can help people with diabetes lower average blood sugar and lose weight, but the benefits only stick around for the short term.
NERD Mini: Predicting the route of the regain train
Here, we give the lowdown on a secondary analysis of a clinical trial exploring what factors can predict regaining weight.
Deep Dive: Is there an optimal way to take omega-3s for improved cardiovascular outcomes in people at high risk?
Over 1 gram of EPA a day keeps cardiovascular problems at bay.
Recovering from osteoarthritis surgery: a joint effort between amino acid supplementation and exercise
Adding amino acid supplementation to mixed-mode exercise may improve pain and preserve muscle compared to exercise alone. More data would be useful, though.