New Data on Obesity and Cancer in Young Persons

Cancer is rising in young persons and it appears that obesity is playing a role. Of course, this is not to say that obesity tells the whole story. Cancer prevalence patterns present a complex puzzle – just as obesity prevalence does.

A Continuing Shift
Toward Younger Persons

Yesterday in CA: A Cancer Journal for Clinicians, Rebecca Siegel and colleagues published a new edition of cancer surveillance statistics for 2024. They report that the category of persons under 50 years of age is the only age group (vs. 50-64 and 65+) to see a rise in cancer incidence between 1995 and 2020. They note obesity is playing a role:

“The shift toward more middle-aged patients likely in part reflects steep decreases in incidence of prostate and smoking-related cancers among older men and increased cancer risk in people born since the 1950s associated with changing patterns in known exposures, such as higher obesity, as well as others yet to be elucidated.”

Colon Cancer

Colorectal Cancer is a big part of this story. In the late 1990s, it was the fourth leading cause of cancer deaths in persons under 50 – both men and women. Now, it is the top cause of cancer deaths for men under 50 and the second leading cause for women in that age group.

Researchers have concluded that obesity is one of the top risk factors for developing colorectal cancer. This type of cancer is 30 percent more likely in persons with obesity. Diverse biological mechanisms help to explain this relationship. These include nutrition, inflammation, hormones, microbiota, and bile acids. But of course, we have much more to learn.

Another relevant observation is that the risk of colorectal cancer goes down after bariatric surgery.

Rising Incidence of Other Obesity-Related Cancers

William Dahut is chief scientific officer at the American Cancer Society. He says the good news in this report is that cancer death rates are falling. But he says the pattern of certain cancers rising in younger persons may reflect an effect of high obesity rates:

“Cancers driven by obesity such as pancreas, kidney, postmenopausal breast cancer, and liver cancers are increasing.”

Click here for the new statistics, here, here, and here for further perspective.

Young Peasant in Blue, painting by Georges Seurat / WikiArt

Subscribe by email to follow the accumulating evidence and observations that shape our view of health, obesity, and policy.

January 18, 2024