Research

Hormonal

Adult weight gain after age 18 increases the risk of postmenopausal breast cancer incidence and mortality, particularly in women who do not use postmenopausal hormones.

If you are postmenopausal, avoiding significant weight gain after age 18 is one of the most effective ways to lower your risk of breast cancer. This is especially true if you do not use hormone replacement therapy. Focus on maintaining a stable weight through diet and physical activity, as weight gain is a stronger predictor of risk than your current body weight alone.

GoodSupportsHIGH confidence
Adult weight gain, which largely reflects an increase in body fat, may be a better variable to assess adiposity and its metabolic consequences than body weight itself... Weight gain after the age of 18 years was unrelated to breast cancer incidence before menopause, but was positively associated with incidence after menopause.
Zhiping Huang et al. · JAMA · 1997

Why this rating

Large prospective cohort (Nurses' Health Study, n=95,256), long follow-up (16 years), and robust statistical adjustment for confounders.

Source

Dual Effects of Weight and Weight Gain on Breast Cancer Risk

Zhiping Huang et al. · JAMA · 1997

DOI 10.1001/jama.1997.03550170037029

cohort · n=95256Cited 830×
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DOI resolved against Crossref · corpus check 2026-06-10

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