Research

Hormonal

Higher early adult BMI (ages 18-30) is inversely associated with breast cancer risk in both pre- and postmenopausal women, suggesting a protective effect of higher adiposity during young adulthood.

Maintain a healthy weight during young adulthood (18-30), as higher early adult BMI may offer some protection against breast cancer later in life. However, avoid adult weight gain, which increases risk.

GoodQualifiesMEDIUM confidence
Greater early adult BMI (ages 18–30 years) was significantly inversely associated with premenopausal breast cancer... Inverse association of similar magnitude was observed for postmenopausal breast cancer
Doris S.M. Chan et al. · Cancer Causes & Control · 2019

Why this rating

Meta-analysis of 13 studies for premenopausal and 18 for postmenopausal women showing significant inverse associations.

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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