Nat Med

Intermittent fasting works in PCOS, but no better than calorie restriction

March 31, 2026

Clinical takeaway: For PCOS patients prioritizing weight loss, time-restricted eating is a practical option. Compared with standard calorie restriction, intermittent fasting adherence was better and outcomes were comparable at an almost 5% weight loss resulting in metabolic and hormonal benefits.

In a 6-month randomized trial of 76 women with polycystic ovary syndrome, a 6-hour eating window led to 4.3% weight loss, similar to 4.7% with calorie restriction, with no meaningful difference between groups. Both approaches reduced energy intake by about 10% (175–180 kcal/day), decreased fat mass and waist circumference, and preserved lean mass.

Fasting insulin and insulin resistance improved in both groups; fasting glucose improved only with calorie restriction, while HbA1c improved only with time-restricted eating. Testosterone decreased in both groups; free androgen index declined only with time-restricted eating. Menstrual regularity, acne, hirsutism, blood pressure, and lipids did not improve.

“We’re looking for other ways of lowering testosterone levels in these women,” said lead author Krista Varady, a nutrition researcher at the University of Illinois Chicago. “Even modest weight loss—around 5%—can meaningfully improve hormone levels and may reduce the need for medication.”

Source:

Corapi S, et al. (2026, March 27). Nat Med. Time-restricted eating for body weight management in women with polycystic ovary syndrome: a randomized controlled trial. https://pubmed.ncbi.nlm.nih.gov/41896647/