Peoria Standard

Colorectal cancer, once considered a disease primarily affecting older adults, is now being diagnosed more frequently in younger individuals. Recent research published in Nature reports that the incidence of early-onset colorectal cancer—cases occurring in people under 50—has doubled across many countries over the past two decades.

Projections from Frontiers in Immunology indicate that global changes in dietary habits are expected to further increase colorectal cancer rates, with estimates suggesting there could be 2.2 million new cases by 2030.

Scientists are increasingly focusing on the gut microbiome as a significant factor in this trend. Daniel Martin, MD, a gastroenterologist with OSF HealthCare, explains: “We think of our microbiome as a separate, living organism within our body. It’s made of billions of bacteria, predominantly growing in our colon. There is a small number of bacteria that does exist in our small bowel, oral pharynx and nasal cavities. Just like we have bacteria on our skin everywhere.”

Research has identified certain harmful gut bacteria species—including strains of E. coli, Klebsiella pneumoniae and Citrobacter koseri—that produce colibactin, a toxin linked to DNA damage and potentially to cancer development.

“They have recognized that there’s a much greater incidence of exposure to this particular strain of E. Coli that makes the Colibactin toxin in patients under the age of 50 who are diagnosed with colorectal cancer,” Dr. Martin says. “There’s also a recognition that Colibactin itself has some DNA-damaging properties within the GI tract. This is likely a direct contributor to the development of early, pre-cancerous dysplastic (abnormal growth) changes that ultimately lead to colorectal cancer in those patients.”

Dietary patterns and antibiotic use may also influence gut health and cancer risk. Dr. Martin notes: “Also thinking about the infections we can have, both as infants and in adulthood. Over the last handful of decades, there’s the exposure of antibiotics,--the antimicrobial medications we’re using to try and treat specific, acute illnesses,” he says. “But those can have a meaningful impact on our gut flora and microbiome in general.”

He points out that ultra-processed foods containing preservatives and dyes could be particularly damaging to gut health while recommending diets rich in beans, nuts, legumes, plants and lean meats.

“If you’re purchasing it in the middle of the grocery store, and it’s vacuum-packaged and sealed, looking nothing like its based product, it’s probably an ultra-processed food in every circumstance,” Dr. Martin says.

“When we are consuming a food product of some kind, if it’s going to go bad quickly, it likely has prebiotics and probiotics in it, and those are good for us. If you leave a banana out on the counter for two weeks, no one wants to eat it because it goes bad. If you leave a Twinkie out on the counter for two years, it hasn’t changed,” Dr. Martin adds.

He also cautions against products high in sugar or artificial additives: “Products like sports drinks, juices and sodas can be laden with sugars, whether real or added (which Dr. Martin refers to as ‘fake sugar’). Many of these products also contain food dyes and preservatives which are bad for our gut health.”

While supplements such as probiotics or prebiotics may offer some benefit for gut health maintenance, their effectiveness varies between individuals due to differences in microbiome composition.

“Currently prebiotic and probiotic supplements are created using the ‘95% confidence interval,’” Dr. Martin says.“This means that out of a sample of people,it was determined that 95%of them would benefit froma certain culture ,probiotic or prebiotic being included inthe product.Because as mentioned earlier,the100% perfect pie chartof what everyone’sgut microbiome looks likeis not currently known.”

For now,the recommended approach remains simple:eat whole foods ,avoid ultra-processed options,and take careofthe trillionsofbacteria working inside us each day.