Research

Hormonal

Obesity in postmenopausal women increases breast cancer risk and recurrence through hormonal mechanisms, specifically elevated estrone, estradiol, insulin, and IGF-1 levels, and reduced sex hormone-binding globulin (SHBG).

For postmenopausal women, excess body fat is not just a storage issue but a hormonal one. Fat tissue produces estrogen and affects insulin/IGF-1 levels, which can fuel breast cancer growth. Reducing body fat may help normalize these hormone levels, potentially lowering the risk of cancer progression.

GoodSupportsHIGH confidence
Obesity is associated with higher concentrations of estrogens in postmenopausal women... obese postmenopausal women have higher blood concentrations of both estrone and estradiol and lower concentrations of sex hormone–binding globulin (SHBG)... Obesity... increases circulating concentrations of insulin and insulin-like growth factor-1 (IGF-1)...
Rowan T. Chlebowski · Journal of Clinical Oncology · 2002

Why this rating

Based on multiple prospective studies and cohort analyses linking hormone levels to breast cancer risk.

Source

Weight Loss in Breast Cancer Patient Management

Rowan T. Chlebowski · Journal of Clinical Oncology · 2002

DOI 10.1200/jco.20.4.1128

narrative_reviewCited 227×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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