The effects of flaxseed supplementation on metabolic status in women with polycystic ovary syndrome: a randomized open-labeled controlled clinical trial

Randomized, open-labeled controlled clinical trial in reproductive-age women with polycystic ovary syndrome diagnosed by Rotterdam criteria. Participants were recruited from the endocrinology clinic at Golestan Hospital in Ahvaz, Iran; for the flaxseed group, 24 participants were randomized and 21 completed the study.

Brown milled flaxseed powder, 30 g/day orally for 12 weeks, supplied in 30 g packets and taken with foods or drinks such as salad, yogurt, or cold beverages. The active regimen was added to lifestyle modification and compared with lifestyle modification alone.

Flaxseed plus lifestyle modification produced better metabolic and anthropometric outcomes than lifestyle modification alone over 12 weeks. Between-group improvements favored flaxseed for insulin concentration, HOMA-IR, triglycerides, HDL cholesterol, hs-CRP, IL-6, adiponectin, leptin, QUICKI, body weight, waist circumference, and BMI, and menstrual regularity also improved. In the flaxseed arm, end-of-study values showed lower weight (73.90 ± 15.20 to 72.99 ± 15.32), waist circumference (88.71 ± 10.99 to 86.88 ± 11.34), BMI (28.38 ± 5.15 to 27.99 ± 5.13), FBS (101.86 ± 12.08 to 94.25 ± 9.78), insulin (12.17 ± 4.5 to 9.79 ± 3.78), and HOMA-IR (3.04 ± 1.19 to 2.32 ± 1.06), with higher HDL cholesterol (34.26 ± 11.75 to 43.3 ± 10.88) and adiponectin (13.04 ± 3.36 to 17.36 ± 4.1). Total testosterone, SHBG, FAI, fasting glucose, and some lipid markers did not differ meaningfully between groups after 12 weeks.

Single-center study with a small active arm sample and a short 12-week duration, which limits precision and long-term inference. The open-label design and concurrent lifestyle modification make it difficult to isolate the independent effect of flaxseed. Some outcomes were unchanged, and adverse events were mild but reported only in the flaxseed group.