Association of metabolic obesity phenotypes with risk of overall and site-specific cancers: a systematic review and meta-analysis of cohort studies

In a new systematic review and meta-analysis, the largest of its kind, scientists from the International Agency for Research on Cancer (IARC) and partner institutions investigated the overall risk of developing cancer and the risk of developing obesity-related cancers among individuals with high adiposity but different metabolic health status, defined as metabolically healthy or metabolically unhealthy. The results were published in the British Journal of Cancer.

The researchers examined 31 publications covering 15 unique cohort studies to assess the strength of associations between cancer and metabolic obesity phenotypes, defined using a combination of adiposity and metabolic dysfunction parameters. They found that individuals classified as metabolically unhealthy overweight or obese had a higher risk of developing any type of cancer (summary relative risk, 1.21; 95% confidence interval, 1.02–1.44) and a much higher risk of developing obesity-related cancers (summary relative risk, 1.42; 95% confidence interval, 1.15–1.74) compared with metabolically healthy normal-weight individuals.

Notably, individuals classified as metabolically unhealthy overweight or obese were found to have a higher risk of postmenopausal breast cancer, colorectal cancer, pancreatic cancer, endometrial cancer, gallbladder cancer, stomach cancer, bladder cancer, liver cancer, kidney cancer, and thyroid cancer compared with metabolically healthy normal-weight individuals.

These findings highlight the importance of combining measures of adiposity with indicators of metabolic dysfunction to identify individuals at higher risk of cancer, in addition to the existing screening practices.

Mahamat-Saleh Y, Aune D, Freisling H, Hardikar S, Jaafar R, Rinaldi S, et al.
Association of metabolic obesity phenotypes with risk of overall and site-specific cancers: a systematic review and meta-analysis of cohort studies
Br J Cancer. Published online 25 September 2024;
https://doi.org/10.1038/s41416-024-02857-7

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