Research

Hormonal

Moderate weight loss (>5% body weight) via long-term calorie restriction (1000 kcal/day) improves endocrine and ovarian function in obese women with PCOS, evidenced by increased SHBG, decreased free testosterone, and restored menstrual regularity.

For obese women with PCOS, achieving a modest weight loss of just over 5% through a sustained, moderate calorie-restricted diet (around 1000 kcal/day) can significantly improve hormonal balance (increasing SHBG, lowering free testosterone) and restore regular menstrual cycles and fertility, without needing to reach an 'ideal' BMI.

ModerateSupportsMEDIUM confidence
These data indicate that moderate weight loss during long-term calorie restriction is associated with a marked clinical improvement which reflects the reduction in insulin concentrations and reciprocal changes in SHBG. The improvement in menstrual function and fertility may therefore be consequent upon an increase in insulin sensitivity which, directly or indirectly, affects ovarian function.
D. Kiddy et al. · Clinical Endocrinology · 1992

Why this rating

Within-group comparison without a control group; observational nature of the weight loss effect.

Source

Improvement in endocrine and ovarian function during dietary treatment of obese women with polycystic ovary syndrome

D. Kiddy et al. · Clinical Endocrinology · 1992

DOI 10.1111/j.1365-2265.1992.tb02909.x

cohort · n=24Cited 921×
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DOI resolved against Crossref · corpus check 2026-06-10

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