Research

Hormonal

Increased body adiposity, specifically higher BMI and adult weight gain, significantly increases the risk of breast cancer in postmenopausal women, particularly for hormone receptor-positive (HR+) tumors.

Maintain a healthy body weight and avoid adult weight gain to reduce breast cancer risk after menopause. This is especially important for preventing hormone receptor-positive breast cancers.

GoodSupportsHIGH confidence
adult weight gain and greater body adiposity increased breast cancer risk in postmenopausal women, and the increased risk was evident for HR+ but not HR− breast cancers
Doris S.M. Chan et al. · Cancer Causes & Control · 2019

Why this rating

Large meta-analysis of 75 studies for BMI and 16 for weight gain in postmenopausal women; consistent positive associations observed.

Source

World Cancer Research Fund International: Continuous Update Project—systematic literature review and meta-analysis of observational cohort studies on physical activity, sedentary behavior, adiposity, and weight change and breast cancer risk

Doris S.M. Chan et al. · Cancer Causes & Control · 2019

DOI 10.1007/s10552-019-01223-w

Meta-analysis · 126 studiesCited 231×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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