How both metabolically healthy and unhealthy 'forms' of obesity increase risk of various obesity-related cancers

New research published in the Journal of the National Cancer Institute shows that both the metabolically healthy and unhealthy ‘forms’ of obesity are associated with an increased risk of various obesity-related cancers, with the relationship stronger in metabolically unhealthy obesity.

In this new research, the authors investigated body mass index jointly and in interaction with metabolic health status in relation to obesity-related cancer risk among 797,193 European individuals.

In women, compared to metabolically healthy women of normal weight, metabolically unhealthy women with obesity had a 21% increased risk of colon cancer, a 3-times increased risk of endometrial cancer, and a 2.5 times increased risk of kidney cancer. Metabolically healthy women with obesity had a 2.4 times increased risk of endometrial cancer and an 80% increased risk of kidney cancer - but the relationship with colon cancer was no longer statistically significant.

In men, compared to metabolically healthy men of normal weight, metabolically unhealthy men with obesity had a 2.6 times increased risk of kidney cancer, an 85% increased risk of colon cancer, and a 32% increased risk of both pancreatic and rectal cancer. Metabolically healthy men with obesity had a 67% increased risk of kidney cancer, and a 42% increased risk of colon cancer, but the relationship with both pancreatic cancer and rectal cancer was no longer statistically significant. In an unusual finding, both metabolically healthy and unhealthy men with overweight (not obesity) had around a 50% increased risk of the blood cancer multiple myeloma - yet neither metabolically healthy or unhealthy men with obesity had an increased risk of this cancer.

Reference:

EUROPEAN ASSOCIATION FOR THE STUDY OF OBESITY MEETING, European Congress on Obesity (ECO2023)