A doctor who studies how a healthy gut can prevent colon cancer does 3 simple things to lower his risk

• Colon cancer is rising in people under 50, and poor gut health could be part of the problem.
• Dr. Neelendu Dey studies whether gut microbes can be harnessed to prevent and treat colon cancer.
• To reduce his colon cancer risk, he eats lots of fiber and plays sports.

More people under the age of 50 are getting colon cancer — but it’s unclear why. A doctor who researches the link between the disease and our gut microbes has a theory.

“I don’t want to give the message that microbes are the entire thing. But we know that there are significant correlations between how much we have of various microbes and cancer,” Dr. Neelendu Dey, an associate professor at Fred Hutchinson Cancer Center in Seattle, told Business Insider.

Trillions of microbes live in our colon lining, and research suggests the more diverse they are the better our health and the lower our chances of developing diseases including colon and other forms of cancer, obesity, type 2 diabetes, and depression.

What we eat and our environment affect the make-up of what’s known as the gut microbiome, for instance, ultra-processed foods and being sedentary are thought to harm it.

Dey’s lab researches how microbes could be used to prevent and treat colon cancer, but everyone’s gut microbiome is unique, he said. By understanding how individual microboes respond to different ingredients, they hope to provide personalized dietary recommendations to prevent precancerous polyps from forming.

Dey is 45, the age the American Cancer Society recommends those with an average risk of colon cancer start getting colonoscopies every 10 years. To lower his colon cancer risk, first and foremost, Dey said he follows official advice to get screened. Those at higher risk, for example, with a genetic predisposition, can talk to their doctor to decide if earlier screening is necessary.

But Dey also makes diet and lifestyle choices to look after his gut microbiome, in the hopes of reducing his colon cancer risk.

“The microbiome, I believe, is a long-term player in improving our health,” he said. “Working with our microbiome is akin to, let’s say, practicing the violin every day if you want to be a good violinist.”

1) Eat fiber at every meal

Dey tries to incorporate some fiber into each of his meals, because there is strong data to suggest they can boost gut health over time. Fiber is found in plant foods such as fruits, vegetables, nuts, beans, and oats, and it feeds the “good” bacteria in the gut.

A 2018 study based on The American Gut Project analyzed the stool samples and eating habits of 10,000 people, and found that those who ate 30 types of plant foods a week had more diverse microbiomes than those who ate 10 or fewer.

Being of South Asian descent, Dey often makes Indian dishes, many of which contain lentils, chickpeas, and spices.

“Good” microbes don’t all eat the same type of fiber. That’s why the authors think eating lots of different types leads to a more diverse microbiome.

2) Avoiding ultra-processed foods

Ultra-processed foods, which can range from foods such as protein bars to oven pizza, are made using ingredients you wouldn’t find in a typical kitchen. They contain additives like emulsifiers and gums, often come in plastic packaging, and are designed to be hyperpalatable, making them easy to overeat.

UPFs have been linked to a host of serious health problems, including colon cancer, but are ubiquitous in modern America. For this reason, Dey tries to avoid them when possible, but knows it’s not realistic to cut them out entirely.

“When I can control it, certainly I do. If I have the time, I would rather grab the apple than the processed bar that contains an apple,” he said.

3) Exercising regularly

Dey is part of a kickball team and exercises independently, too. He does this because, as well as boosting heart health and helping him maintain a healthy weight, working out is beneficial for gut health.

Regular exercise can help food move through the digestive system more quickly, reducing the time the colon is exposed to toxins. Studies suggest that working out can also increase the number of “good” microbes in the gut, improving diversity.

“Certainly, exercise — I find, and I think others find — has huge benefits for gut health,” Dey said.