Research

Hormonal

In postmenopausal women with a normal baseline BMI (<25.0), gaining more than 5% of body weight during follow-up is associated with an increased risk of invasive breast cancer.

Postmenopausal women with a normal weight should be vigilant about avoiding significant weight gain (more than 5% of body weight), as this increases breast cancer risk. This highlights that weight stability is important even for those who are not currently overweight.

StrongQualifiesHIGH confidence
Women with a baseline BMI of less than 25.0 who gained more than 5% of body weight over the follow-up period had an increased breast cancer risk (HR, 1.36; 95% CI, 1.1-1.65)
Marian L. Neuhouser et al. · JAMA Oncology · 2015

Why this rating

Derived from the same large-scale WHI trial with rigorous measurement.

Source

Overweight, Obesity, and Postmenopausal Invasive Breast Cancer Risk

Marian L. Neuhouser et al. · JAMA Oncology · 2015

DOI 10.1001/jamaoncol.2015.1546

rct · n=67142Cited 629×
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DOI resolved against Crossref · corpus check 2026-06-10

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