• Colon cancer rates for people under age 50 are going up across countries both rich and poor.
• In the US, rates for older adults are declining, while early-onset colon cancer is on the rise.
• Scientists are starting to uncover clues about how modern diets and lifestyles play a role.

Colon cancer is quickly becoming a young person's disease in countries around the world.

A new study released Wednesday in the Lancet Oncology documents rising rates of early-onset colorectal cancer across rich, highly-industralized parts of North America and Europe, and in middle-income areas worldwide.

"We found this trend is not just about high-income, Western countries," lead study author and cancer researcher Hyuna Sung told Business Insider. "It reaches the parts we didn't see before, such as South America and Asia."

During the 5-year period from 2013 to 2017, colon cancer rates in young people went up in 27 of 50 countries Sung's team examined worldwide. Though the study only includes one country in Africa (Uganda), it is still some of the most recent, comprehensive data available on colon cancer rates around the globe. And it shows colon cancer rates spiking in young people living in countries like Turkey, Ecuador, and Chile.

The trend is not hitting all countries equally, though. While in the US, early-onset colon cancer rates continue to rise to unprecedented levels, there are outliers in the data, like Italy, Spain, and Latvia, where the rates appear relatively unchanged year over year.

"This study is quite expected," associate professor Ganesh Halade from USF Heart Health Institute, who was not involved in this study, told BI, while poring over the new data, and noting the rising rates across several continents. "Fundamentally, our diet is changed"

Halade's own colon cancer research, published earlier this week, identified how ultra-processed foods can fuel colon cancer, wreaking havoc on the immune system, and worsening inflammation.

"It's very obvious the way that this disease trend is going on right now," he said. "We need to go back and consider our diet, sleep, and exercise."

Why colon cancer is striking younger people in richer countries

It still seems to be the case that the richer a country gets, the more young people are at risk of developing colon cancer. Countries with some of the steepest gains in under 50 colon cancer cases in recent years include Australia, New Zealand, the US, South Korea and Japan.

"Children and adolescents in these highly industrialized and urbanized countries were probably among the earliest to uptake detrimental dietary exposures and sedentary lifestyles associated with economic wealth," the study authors wrote.

In other words, driving around in a car, sitting at a desk, and eating more convenience food every day for decades on end may not be great for our overall health, and might have some connections to these cancer trends. Once inflammation skyrockets, Halade said, cancer has an easier time both sprouting and thriving. His anecdotes? More sleep, movement, and home-cooked food.

There seems to be a pronounced uptick in the incidence of early-onset colon cancer among people born after 1950, suggesting that there are lifestyle and environmental exposures impacting Gen X, millennials, and Gen Z in ways their baby boomer parents and predecessors like the Greatest Generation didn't experience.

At the same time, thanks to more cancer screenings and less smoking, colon cancer rates in older adults are going down in many rich countries around the world, including the US, Canada, Australia, New Zealand, the UK, South Korea, and Israel.

What we eat and how we live matters, it seems

Scientists are still endeavoring to untangle exactly what is driving the early-onset colon cancer risk, but there seem to be some clear signals in the data about the food system we live in. Another new study released earlier this week suggested that our modern diets, filled with candy, sugary drinks, and processed foods, don't have enough of the healthy fats and nutrients our bodies need to keep cancer-driving inflammation in check.

Foods rich in omega-3, like leafy greens, fatty fish, nuts and seeds can help prevent the inflammatory processes that over time lead to cancer. But sweets, chips, sausages, and packaged cakes seem to fuel tumors, while also crowding out more unprocessed, healthier choices in our diets.

Still, food can't be the whole story. It's clear that a family history of colon cancer, as well as the unique dance your genetics and your environment play, have key roles in your personal level of colon cancer risk. Experts are looking into environmental factors like air pollution, microplastics, and more sedentary lifestyles for clues about what else may be driving the increase in young colon cancer.

• A new study offers more evidence linking cancer to inflammation from diets high in processed foods.
• Analysis found tumors were fueled by inflammatory compounds and a lack of compounds linked to healing.
• Researchers are looking to foods like leafy greens and fish to pinpoint disease-fighting molecules.

Ultra-processed foods may be fueling a rise in colon cancer cases — but healthy foods could unlock new ways to prevent or treat the disease, new research suggests.

Researchers from the University of South Florida and Tampa General Hospital Cancer Institute analyzed more than 100 tumor samples from patients. They were looking for compounds called bioactive lipids, molecules that can increase or decrease inflammation in the body.

The research team found that tumor samples contained a high proportion of these inflammation-causing compounds compared to healthy tissue.

Previous evidence has linked increased inflammation to diets high in processed food like chips, sausages, packaged desserts, and refined carbs.

Processed food shows up almost everywhere in our diets, and evidence increasingly suggests it's a factor in worsening health. At the same time, colon cancer cases are on the rise in younger people, and it's now the second-leading cause of cancer-related death in the US.

The researcher team also noted that the tumors were lacking in molecules associated with healing and lowering inflammation.

The inside look at the tumors could give scientists the tools to fight cancer by trying to balancing the body's immune response, slowing or stopping tumor growth by cutting back on inflammatory compounds and boosting healthy ones.

One source of these kinds of molecules is our diet, from foods like leafy greens and seafood rich in omega-3 fatty acids.

"If the molecules are coming from processed food products, they directly imbalance the immune system and drive chronic inflammation," Ganesh Halade, co-author of the study and professor at the University of South Florida Health Heart Institute said in a press release. "Our bodies are designed to actively resolve inflammation through bioactive lipid compounds derived from the healthy fats, like avocados, that we consume."

Fighting cancer with fish oil

The study, published December 10 in the journal Gut, is the first from a project funded by a five-year, $3.1 million grant from the National Institutes of Health.

The results are helping researchers better understand how food may influence cancer risk, Dr. Timothy Yeatman, senior author of the study and professor of surgery at the University of South Florida, said in a press release.

Cancer is like a "chronic wound that won't heal," and a daily diet of ultra-processed foods can make it harder for the body to fight off tumors because of the increased inflammation, Yeatman said.

While it's not news that spinach and seafood is better for you than doughnuts and soda, pinpointing the link between food and inflammation unlocks more effective strategies to stave off disease in the future.

For example, the Tampa General Hospital Cancer Institute has conducted early trials of a modified form of fish oil with promising results for reducing inflammation, according to the press release.

"This has the potential to revolutionize cancer treatment, moving beyond drugs to harness natural healing processes," Yeatman said. "It's a vital step toward addressing chronic inflammation and preventing diseases before they start."

In the meantime, there's evidence that your best bet for a longer, healthier life is sticking to a diet of mostly whole, unprocessed foods like veggies, fruits, legumes, lean proteins, and whole grains.