Research

Hormonal

In postmenopausal women who have never used hormone replacement therapy, greater waist circumference is significantly associated with an increased risk of invasive breast cancer, independent of overall body mass index.

If you are postmenopausal, your body shape matters for breast cancer risk, not just your weight. Specifically, carrying more weight around your waist increases your risk, even if your overall weight (BMI) is healthy. This risk is most pronounced if you do not take hormone replacement therapy. To mitigate this, focus on reducing central adiposity through lifestyle changes, as waist circumference is a stronger predictor of risk than BMI alone in this group.

GoodQualifiesHIGH confidence
Among women who had never used postmenopausal hormones... there was a stronger positive association between waist circumference and postmenopausal breast cancer... The multivariate relative risks for the fourth and fifth quintiles of waist circumference were 1.52 (95 percent CI: 1.02, 2.27) and 1.88 (95 percent CI: 1.25, 2.85)... The associations were only slightly attenuated after further adjustment for 1986 body mass index (for the fourth and fifth quintiles, RR = 1.50 (95 percent CI: 0.98, 2.29) and RR = 1.83 (95 percent CI: 1.12, 2.99), respectively).
Zhiping Huang et al. · American Journal of Epidemiology · 1999

Why this rating

Large prospective cohort (Nurses' Health Study, n=47,382), long follow-up, rigorous adjustment for confounders, but observational design prevents causal proof.

Source

Waist Circumference, Waist: Hip Ratio, and Risk of Breast Cancer in the Nurses' Health Study

Zhiping Huang et al. · American Journal of Epidemiology · 1999

DOI 10.1093/oxfordjournals.aje.a009963

cohort · n=47382Cited 224×
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DOI resolved against Crossref · corpus check 2026-06-10

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