Eight-hour time-restricted feeding improves endocrine and metabolic profiles in women with anovulatory polycystic ovary syndrome.
Level 4 - case-series / case-control
Single-arm uncontrolled before-and-after trial
PubMed 33849562 · doi:10.1186/s12967-021-02817-2
What was done
Eighteen women aged 18–31 with anovulatory polycystic ovary syndrome (PCOS) were enrolled in a 6-week single-arm intervention consisting of a 1-week baseline weight stabilization period followed by 5 weeks of 8-hour time-restricted feeding (TRF). Fifteen participants completed the study. Researchers assessed changes in anthropometrics, body composition, reproductive hormones (LH, FSH, testosterone, SHBG), glucose and insulin dynamics (HOMA-IR, oral glucose tolerance test AUCs), inflammatory markers, liver enzymes, and menstrual cycle patterns.
What was found
The abstract reports statistically significant changes following the 5-week TRF intervention for body weight, BMI, body fat mass, body fat percentage, visceral fat area, total testosterone, SHBG, free androgen index, fasting insulin, HOMA-IR, insulin AUC, insulin/glucose AUC ratio, ALT, hsCRP, and IGF-1 (exact numbers and effect sizes are not reported in the abstract). Improvement in menstrual cycle irregularity was observed in 73.3% (11/15) of participants.
Why it matters
This pilot study suggests that time-restricted feeding is feasible and may improve hyperandrogenemia, insulin resistance, and menstrual regularity in anovulatory PCOS.
Limits
The trial had a very small sample size (15 completers), a short duration (5 weeks of TRF), and lacked a control group, making it impossible to separate the specific effects of time-restricted feeding from general caloric deficit, regression to the mean, or study participation effects. Exact numerical results and confidence intervals for metabolic and endocrine outcomes were omitted from the abstract.
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