Research

Hormonal

Higher body mass index (BMI) at age 18 is associated with a lower risk of both premenopausal and postmenopausal breast cancer.

Maintaining a healthy weight in your late teens and early adulthood may offer long-term protection against breast cancer. While extreme leanness is not necessarily better, avoiding being underweight might be beneficial. Focus on overall health rather than extreme thinness.

GoodSupportsHIGH confidence
Higher BMI at the age of 18 years was associated with lower breast cancer incidence both before and after menopause.
Zhiping Huang et al. · JAMA · 1997

Why this rating

Large prospective cohort with long follow-up and 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×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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