Research

Hormonal

In postmenopausal women, the association between central adiposity (waist circumference) and breast cancer risk is significantly modified by hormone replacement therapy use, with the association being strongest in never-users and non-significant in current users.

If you are postmenopausal and take hormone replacement therapy, your breast cancer risk is elevated regardless of your waist size. However, if you do not take hormones, keeping your waist circumference low is a critical way to reduce your risk. The protective effect of a smaller waist is most visible in those not taking hormones.

GoodQualifiesMEDIUM confidence
Among current postmenopausal hormone users... no association was observed between waist circumference and risk of postmenopausal breast cancer... The interaction between waist circumference and postmenopausal hormone use was of borderline significance (p = 0.06, 2 df).
Zhiping Huang et al. · American Journal of Epidemiology · 1999

Why this rating

Large cohort, clear stratification, but interaction p-value is borderline (0.06) for waist circumference, though significant for waist:hip ratio.

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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