Research

Hormonal

Post-diagnosis obesity (BMI >= 30 kg/m2) is associated with a 52% increase in all-cause mortality and a 2.28 times greater risk of breast cancer-specific mortality compared to normal BMI.

Maintaining a normal BMI after a breast cancer diagnosis is strongly associated with better survival. Obese women (BMI >= 30) had more than double the risk of dying from breast cancer compared to those with a normal BMI. Survivors should aim to achieve and maintain a healthy weight through diet and exercise, as this is linked to significantly improved mortality outcomes.

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Women categorized as obese (BMI >= 30 kg/m2) before a breast cancer diagnosis had a 52% increase in all-cause mortality risk... Risk for death from breast cancer was 2.28 times greater for women classified as obese at CWLS enrollment compared with those with a BMI in the reference range.
Hazel B. Nichols et al. · Cancer Epidemiology Biomarkers & Prevention · 2009

Why this rating

Large cohort, long follow-up, adjusted for confounders, but observational.

Source

Body Mass Index Before and After Breast Cancer Diagnosis: Associations with All-Cause, Breast Cancer, and Cardiovascular Disease Mortality

Hazel B. Nichols et al. · Cancer Epidemiology Biomarkers & Prevention · 2009

DOI 10.1158/1055-9965.epi-08-1094

cohort · n=3993Cited 263×
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DOI resolved against Crossref · corpus check 2026-06-10

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