Time-restricted eating for body weight management in women with polycystic ovary syndrome: a randomized controlled trial

Abstract Polycystic ovary syndrome (PCOS) is an endocrinological disorder characterized by weight-loss resistance. Time-restricted eating (TRE) has become a popular weight-loss tool. However, the efficacy of TRE for weight management in PCOS remains understudied. We evaluated the effectiveness of TRE compared with standard care (daily calorie restriction (CR)) and a no-intervention control in women with PCOS. Seventy-six participants were randomly assigned to one of three groups for 6 months: a 6-hour TRE regimen (all meals consumed between 1 p.m. and 7 p.m., without calorie tracking), a CR plan (25% daily energy restriction) or a control group with no dietary changes. The primary endpoint was percent change in body weight at 6 months. By month 6, body weight significantly decreased in the TRE group (−4.32% (95% CI, −6.20, −2.44), P < 0.01) and the CR group (−4.66% (95% CI, −7.13, −2.19), P < 0.01), relative to controls, with no difference between the TRE and CR groups (0.34% (95% CI, −2.15, 2.83), P = 0.79). No serious adverse events were reported. Our results show that in women with PCOS, TRE induced greater weight loss than the controls and was comparable to that achieved with daily CR. ClinicalTrials.gov registration: NCT05629858. This is a preview of subscription content, access via your institution Access options Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription $32.99 / 30 days cancel any time Subscribe to this journal Receive 12 print issues and online access $259.00 per year only $21.58 per issue Buy this article - Purchase on SpringerLink - Instant access to the full article PDF. USD 39.95 Prices may be subject to local taxes which are calculated during checkout Similar content being viewed by others Data availability Due to privacy concerns, the datasets used in this study are not publicly available. However, researchers can request access to specific data for academic use only within 24 months of the publication date. Data will be anonymized and provided in summary format (not individual-level data) before sharing. Data access requests should be directed to the corresponding author (varady@uic.edu) to discuss the data of interest and obtain approval. The corresponding author will reply to data requests within a 1-month time frame. Source data are provided with this paper. Code availability The scripts for the statistical analysis are available upon request. Access requests should be directed to the study statistician (shaina.alexandria@northwestern.edu). References Dumesic, D. A. et al. 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Cienfuegos, S. Corapi and K.A.V. Funding acquisition: K.A.V. Investigation: S. Cienfuegos, S. Corapi, M.-C.R., J.L., M.A.d.L., V.P., S.L., M.E., K.G., L.T.-H., V.M.O., J.S. and A.P.V. Project administration: S. Cienfuegos and S. Corapi. Formal analysis: S.J.A. Writing—original draft: K.A.V., S. Cienfuegos and S. Corapi. All authors reviewed, revised and agreed the final version of the paper. Corresponding author Ethics declarations Competing interests K.A.V. received author fees from Hachette Book Group for the book The Every Other Day Diet and from Pan MacMillan Publishing for the book The Fastest Diet. The other authors declare no competing interests. Peer review Peer review information Nature Medicine thanks Daniela Koppold, Jonatan Ruiz, Yushu Shi and Judy Zhong for their contribution to the peer review of this work. Primary Handling Editor: Ashley Castellanos-Jankiewicz, in collaboration with the Nature Medicine team. Additional information Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Extended data Extended Data Fig. 1 Adherence to the diet interventions. Panel A represents adherence to the time restricted eating (TRE) intervention. Data are expressed as mean (SD) days per week that participants reported being adherent with the 1:00 pm to 7:00 pm eating window; only observed values included. A total of 20/26 TRE participants returned adherence logs. Panel B represents adherence to the daily calorie restriction (CR) intervention. Data are expressed as the proportion of participants whose actual energy intake, determined via food recalls, was within 200 kcal of their prescribed daily energy goal; only observed values included. A total of 19/26 CR participants returned food records. Abbreviations: CR: Calorie restriction group, TRE: Time restricted eating group. Extended Data Fig. 2 Difficulty in adhering to the time restricted eating versus calorie restriction intervention. Panel A represents the proportion of time restricted eating participants who reported finding their assigned diet intervention easy, moderately easy, moderately difficult, or difficult to adhere to. A total of 19/26 TRE participants returned the survey. Panel B represents proportion of calorie restriction participants who reported finding their assigned diet intervention easy, moderately easy, moderately difficult, or difficult to adhere to. A total of 18/26 CR participants returned the survey. The proportion of TRE participants (39%) who reported finding their diet intervention “easy to adhere to” did not differ significantly (P = 0.093) from the proportion of CR participants (17%) who reported finding their diet intervention “easy to adhere to.” Two-sided P value from chi-square test. Extended Data Fig. 3 Experimental design. Abbreviations: CON: control group, CR: Calorie restriction group, PCOS: Polycystic ovary syndrome, TRE: Time restricted eating group. Supplementary information Source data Source Data Fig. 2 (download XLSX ) Source data for Fig. 2. Source Data Extended Data Fig. 1 (download XLSX ) Source data for Extended Data Fig. 1. Source Data Extended Data Fig. 2 (download XLSX ) Source data for Extended Data Fig. 2. Rights and permissions Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. About this article Cite this article Corapi, S., Runchey, MC., Lyons, J. et al. Time-restricted eating for body weight management in women with polycystic ovary syndrome: a randomized controlled trial. Nat Med (2026). https://doi.org/10.1038/s41591-026-04316-7 Received: Accepted: Published: Version of record: DOI: https://doi.org/10.1038/s41591-026-04316-7