Research

Hormonal

Weight gain in adulthood is strongly associated with an increased risk of postmenopausal breast cancer in women who have never used hormone replacement therapy (HRT).

For postmenopausal women, especially those not using hormone replacement therapy, avoiding weight gain in adulthood is a key strategy for reducing breast cancer risk. Each 5 kg of weight gain is linked to an 11% higher risk. This highlights the importance of long-term weight management, not just immediate weight loss.

WeakSupportsHIGH confidence
The risk of postmenopausal breast cancer among women who have never used HRT increased by 11% for each 5 kg of weight gain in adulthood (1.11, 1.09 to 1.13)
Maria Kyrgiou et al. · BMJ · 2017

Why this rating

Classified as 'strong evidence' based on the study's rigorous criteria.

Source

Adiposity and cancer at major anatomical sites: umbrella review of the literature

Maria Kyrgiou et al. · BMJ · 2017

DOI 10.1136/bmj.j477

Meta-analysis · 204 studiesCited 826×
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DOI resolved against Crossref · corpus check 2026-06-10

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