Study Links Body Types to Colorectal Cancer Risk

Cancer is one of the most severe diseases. Researchers have been trying to find a solution to this disease for decades now. A new study recently says that people with two particular body types might be prone to cancer more than others. They say people with obesity or tall humans with massive fat accumulation around their middle are at an increased risk of colorectal cancer. Repeated studies have linked obesity and height to increased cancer risk, including colorectal cancer. Now, a team of researchers has analyzed health data reported for 329,828 U.K. Biobank participants of Caucasian, African, Asian, and Chinese ancestries, showing that this pattern exists across all of them. 

For the study published in Science Advances, researchers looked at the impact of height, obesity, and fat distribution on an individual’s risk of colorectal cancer. Participants were split into four groups based on their body shape as defined by height and fat distribution. They used data collected on BMI (body mass index), height, weight-to-height ratio, and waist and hip circumference to determine which group an individual fits into. Groups were PC1( obese), PC2(tall with distributed fat mass), PC3 (centrally obese), and PC4 (low height with high weight). 

They found that individuals in the PC1 group had a 10 percent higher risk of colorectal cancer in this cohort, and those in the PC3 group had a 12 percent higher risk of colorectal cancer, which rose to 18 percent higher for women. 

The other two groups had a small but significant increase in their risk of cancer. Researchers said that the most used indicators of body fat, like BMI or waist circumference, are underestimating cancer risk due to unhealthy weight. Despite their usefulness, these indicators group individuals with similar body mass indexes but with different body shapes into the same category, while we know that people with the same body mass index can have very different cancer risks. Their findings confirmed that fat accumulation around the middle of the body or the abdomen was linked to a higher risk of colorectal cancer. Researchers identified 3,414 genetic variants associated with body shape. These were found to be differentially expressed in different tissues across the four different body categories created by the researchers. 

Those with genetic variants associated with a PC1 body shape had increased expression in the brain and pituitary gland tissues, and those associated with a PC3 body shape had increased genetic expression in the adipose tissue, breast, nerve, blood vessel tissues, and female reproductive organs. 

The study’s authors propose that the role of height in cancer risk has been overstated in previous research that did not consider the waist-to-height ratio and, therefore, central adiposity. Researchers still want to identify genes underlying the relationship between body shapes and genetic expression to help explain the mechanisms underpinning their latest findings. 

Journal Reference -Peruchet-Noray, L., Sedlmeier, A. M., Dimou, N., Baurecht, H., Fervers, B., Fontvieille, E., … Freisling, H. (2024). Science Advances, 10(16). doi:10.1126/sciadv.adj1987