Research

Hormonal

Obesity increases the risk of post-menopausal breast cancer primarily through increased bioavailability of oestrogens due to adipose tissue aromatization and reduced sex hormone-binding globulin (SHBG).

For post-menopausal women, maintaining a healthy weight is crucial for reducing breast cancer risk. This risk is driven by higher levels of bioavailable oestrogens. If you are not using hormone replacement therapy, weight management is a key protective factor.

GoodSupportsHIGH confidence
obese post-menopausal women have higher conversion rates of sex hormones compared with non-obese post-menopausal women... obesity-related hyperinsulinaemia inhibits hepatic secretion of sex hormone-binding globulin... increase in bioavailable oestradiol and testosterone... may increase cell proliferation and inhibit apoptosis
Tobias Pischon et al. · Proceedings of The Nutrition Society · 2008

Why this rating

Supported by multiple studies and biological plausibility, though epidemiological evidence for plasma levels of IGF-1 is noted as inconsistent.

Source

Obesity and cancer

Tobias Pischon et al. · Proceedings of The Nutrition Society · 2008

DOI 10.1017/s0029665108006976

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DOI resolved against Crossref · corpus check 2026-06-10

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