Women with polycystic ovary syndrome likely receive no benefit from daily omega-3 fatty acid supplementation, according to a meta-analysis of three randomized controlled trials.

“Reducing the levels of serum insulin and increasing insulin sensitivity are considered to be of paramount importance for therapeutic targets in PCOS,”Alirez Sadeghi, of the department of cellular and molecular nutrition at the School of Nutritional Sciences and Dietetics at Tehran University of Medical Sciences, Iran, and colleagues wrote. “Omega-3 fatty acids may lead to insulin sensitivity by producing and secreting anti-inflammatory adipokines, such as adiponectin, and also through reducing inflammation and proinflammatory cytokines. Although it is said that omega-3 fatty acids have positive effects on insulin resistance, various studies have indicated contradictory results.”

Sadeghi and colleagues analyzed data from three studies that measured the association between oral omega-3 supplementation and insulin resistance inwomen with PCOS. Studies were conducted in Australia, Iran and the United States, and included 72 women with PCOS and 73 controls. All studies were double blind and published between 2009 and 2012 with follow-up between 6 and 8 weeks. In all three studies, PCOS groups received 1.2 g to 3.6 g daily omega-3 supplementation containing eicosapentaenoic acid and docosahexaenoic acid (median, 2.7 g); control groups received an oral placebo (olive oil, soybean oil or other placebo). Researchers assessed plasma fatty acid composition in one study; participants maintained their usual diet during intervention in two of the studies; daily energy intake was assessed at baseline and end of intervention in two studies.

In women with PCOS, researchers found that omega-3 fatty acid supplementation did not affect insulin plasma level (mean difference: 6.018; 95% CI, –3.347 to 15.382) or homeostasis model assessment of insulin resistance (HOMA-IR; mean difference: 0.276; 95% CI, –1.428 to 1.981), with high heterogeneity observed for both. The researchers noted that samples sizes in the included studies were low, and further, high-quality randomized controlled trials are needed to validate the findings. – by Regina Schaffer