Young colon cancer linked to specific fats in ultra-processed foods

It's not the same old colon cancer anymore. Research presented this week at the world's largest cancer conference points to unique factors that distinguish young colon cancer from traditional cases.

Scientists and doctors are scrambling to understand this phenomenon, which has been on the rise and getting worse since the 1990s. This year, colon cancer became the leading cause of cancer death in people under 50, and the only cancer that is becoming more deadly in that age group, not less.

"Something is just not the same with these early-onset colon cancer patients," Dr. Deepak Vadehra, chief of gastrointestinal oncology at ChristianaCare Health System in Delaware, told Business Insider. Vadehra has spent several years studying how young colon cancer may be different, in a bid to improve treatment outcomes. "The why — that's what we want," he said.

A few new clues are emerging.

At the annual American Society of Clinical Oncology conference in Chicago this week, several presenters coalesced around the idea that young-onset colorectal cancer is a distinct disease from the kind that tends to hit people in their late 60s or early 70s.

These younger cases, increasingly being diagnosed in people under 50 around the globe, appear to have more links to our modern environment: the big changes in what we eat and how we live, that have taken place since Baby Boomers were born.

A string of early-stage research presented at ASCO this year is pointing toward inflammation tied to ultra-processed foods and a lack of microbial diversity in our guts as two emerging "whys" that may help explain the trend.

Too much oil and grease, not enough nuts and fish

Dr. Ning Jin at The Ohio State University has gone straight to the source to better understand young colon cancer. She's investigated a small set of 16 tumors from young-onset colorectal cancer patients and compared them to 26 older patients' tumors. Her work has pinpointed 11 cancer genes that are more prevalent in young people, revealing what she calls a new genetic "fingerprint" for young colon cancer.

"Our study showed that early-onset colorectal cancer is a biologically unique disease," Jin told Business Insider. "The cancer behaves differently."

She said key differences in young cancer involve inflammatory pathways in the body, pathways that may be activated by the modern, unbalanced way we eat.

Modern diets tend to include an overabundance of omega-6 fatty acids from ultra-processed foods that are often loaded with vegetable oils, and not enough essential omega-3, which you can find in fatty fish, nuts, and seeds.

Jin's latest work, presented at ASCO, is bolstering her theory that ultra-processed foods ignite an "inflammatory metabolic pathway" that can make cancer more aggressive.

The finding lends more evidence to the idea that our modern environment — from the foods we eat, to the air we breathe, and the products we use — may stoke colorectal cancer in new ways, and from a very early age.

"I think it is a very complex interplay of things," Vadehra said. "There's the real concern that a lot of the things that we used to just do and go about without thinking twice, maybe we start thinking and being a little bit more scrutinizing about the choices that we make."

Jin hopes her work can provide a framework for developing new blood tests that could one day help identify who's most at risk of developing young colon cancer, decades before colonoscopies are recommended.

Not enough good bugs in the gut

Scientists are also growing increasingly concerned about the bugs that colonize young patients' guts. If bad bugs are crowding out the good ones in early life, could it be making young colons less cancer-resistant?

"In the last 50 years we've become a lot cleaner," cancer geneticist Rachel Purcell, from the University of Otago in New Zealand, told Business Insider. "That's a good thing in some ways, but in another way, it's actually not, because we need to be exposed to microbes to develop a healthy, functioning immune system and that immune system is really important in clearing tumor cells."

Purcell, who studies how harmful bacteria can help colorectal cancer thrive, has identified a specific kind of toxic E. coli, which is more common in young colon cancer tumors, called cytotoxic necrotizing factor 1.

It's still unclear where this new toxin is coming from, or why it's more present in young colon cancer cases than old. Previous research linked a second toxic bacteria, colibactin, to young colon cancer, a trend scientists suspect is seeded through infections in very early life, before kids reach age two.

"All the bugs in our gut, they're vying for space and nutrients, and if we're not feeding the good ones, it does allow our pathogenic microbes to flourish," Purcell said. "Looking at microbiomes, they've just become so much less diverse, and that just makes us vulnerable."

How do we put this science into practice?

The general public is clamoring for answers. The food industry is seeing surging skepticism around ultra-processed foods and demand for "gut-healthy" products.

But oncologists have mixed feelings about the new research. While it is interesting, it doesn't change much for how they treat the disease now, or help identify who's most at risk.

"We are seeing some differences when you compare the early-onset to later-onset population, and these are important, but they're not completely polarizing," Dr. Stacey Cohen, an oncologist who studies how genetics impact gastrointestinal cancers and treatment at Fred Hutch Cancer Center in Seattle, told Business Insider. "That's great for science, but it doesn't really change the person that then walks into your office tomorrow. Whether they're 26 or 56, you're going to end up kind of treating them the same," she said.

Fibermaxxing with nuts, seeds, and whole grains can help your gut thrive

While the research on what's driving young colon cancer is still in its infancy, and doctors stress a lot of young-onset colorectal cancer diagnoses may come down to pure bad luck, scientists agree there are a few evidence-based lifestyle tips for the general public to follow.

1. Avoid ultra-processed junk foods, especially sugary drinks, and aim to eat more nutrient-dense real foods. Fiber is fantastic for gut health, and it's plentiful in fruits, vegetables, nuts and seeds.

"Healthy gut bacteria need to have the fiber so that they can ferment, they can produce more beneficial metabolites," Jin, the oncologist, said.

A diet rich in fiber and whole foods will inherently drive down inflammation, and cut down a person's intake of additives like emulsifiers, which may also play a role, Jin said.

2. Avoid overuse of antibiotics, especially if you have a viral infection, as antibiotics won't help cure it, and they essentially strip your gut microbiome naked of good bugs.

"Try to avoid antibiotics — unless you really, really need them," Purcell said.

Cancer doctors and researchers hope that these new clues will eventually lead to better testing and treatments for young colon cancer, all more targeted to some unique biological processes that may be underway in this novel disease.

"We're still learning a lot about how to treat cancer and how to figure out what are some of the risk factors," Cohen said.