8 risk factors for colon cancer, from diet to drinking habits, according to a doctor

Too much time spent sitting is a risk factor for multiple cancers, including colon cancer, according to research.

In contrast, physical activity seems to have a protective effect, helping to lower the risk of colon cancer, studies suggest. There's good evidence that higher cardiovascular fitness is linked to lower risk of getting colon cancer and of dying from colon cancer, too,

Experts currently recommend getting a few hours of exercise each week, whether that's walking, playing sports, lifting weights, or anything else that raises your heart rate.

"Increase your physical activity — get at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity activity each week," Davis said.

What you eat is also an important factor in your odds of developing colon cancer. Eating plenty of fruits, vegetables, and whole grains can help you get enough fiber, an important nutrient for preventing chronic illnesses like cancer, evidence suggests.

"Fiber is important because it keeps the digestive system working well, and it lowers inflammation, which can lead to cancer and other diseases," Davis said.

Studies have linked diets lacking in fiber and plant foods — such as the standard American diet high in processed food, refined grains, and sugar —to higher risk of cancer, too.

Eating well can also help you have better odds of beating cancer if you do get it, Davis said.

"Diet plays a major role in not only preventing cancer, but it affects treatment and survivorship too," Davis said. "There is no one-size-fits-all diet, but there are healthy eating guides."

No matter your eating style, good goals for cancer prevention are to make plant foods about 2/3 of your plate, according to Davis.

A colorful mix of fruits, veggies, grains, nuts, and seeds can help you get a variety of nutrients and health benefits, she said.

While plant foods like veggies seem to be protective against colon cancer, some evidence suggests animal products like red and processed meat have the opposite effect, raising your risk.

In particular, processed meat is consistently linked to worse health outcomes for several illnesses, including heart disease as well as colon cancer.

Red meat is more ambiguous, with some studies suggesting too much may be unhealthy, and others indicating it could be fine in moderation.

You may not need to cut meat out entirely, but experts suggest limiting your consumption of red meat to a few servings a week, and nixing foods like bacon, sausages, and cold cuts.

"If you choose to eat red meat, eat no more than 12-18 ounces per week, and avoid processed meats as much as possible," Davis said.

Also be mindful of how you prepare your meats, since evidence suggests high temperatures can increase the level of cancer-causing compounds in the meat.

There's convincing evidence that moderating your alcohol consumption can help reduce your risk of colorectal cancer, Davis said.

Alcohol is a known carcinogen, or cancer-causing substance, which can raise your risk of multiple types of cancer, according to the American Cancer Society.

What's less clear is how much alcohol is safe. Most experts advise having no more than one alcoholic drink a day for women, and no more than two a day for men, per the US Dietary Guidelines.

However, some studies have found that there is no safe amount of alcohol, and even a daily drink or two can increase the risk of cancer.

It's common knowledge that smoking can cause cancer, but it isn't just your lungs that are in danger, since it significantly increases your risk of colon cancer as well.

One of the best things you can do is avoid smoking entirely, or quit if possible, according to Davis.

"Don't smoke, and if you do, stop smoking," she said.

Body mass index (BMI), or ratio of height to weight, can be another indicator of above-average colon cancer risk, according to Davis.

Multiple studies have found a higher risk of colon cancer is associated with having a BMI above 25 (considered "overweight") or 30 (in the "obesity" range), with some evidence finding nearly double the risk in people with a higher BMI.

BMI is controversial because it's not always an accurate measure of health, and some experts say it contributes to weight stigma and worse healthcare access for people with larger bodies.

However, managing your weight may be protective against colon cancer risk, particularly in conjunction with the other lifestyle changes like diet, exercise, smoking, and alcohol use, research suggests.

And some evidence indicates how much body fat you have, and where it's located, may be an important factor, with belly fat seeming to pose the biggest risk.

"Maintain a healthy body weight," Davis said. "Avoid overall body fat, especially fat around your waist."

Your overall health, and digestive health specifically, can also influence your odds of developing colon cancer.

Inflammatory bowel disease, Crohn's disease, and ulcerative colitis all affect the intestines and can make you at higher risk for colon cancer, according to the CDC.

Having type 2 diabetes is also linked to a higher risk, even independently of other risk factors such as BMI and exercise habits.

Talk to your doctor about your medical history so they can better understand and recommend a prevention plan, according to Davis.

"It's important to see a doctor who understands your personal risks and the nuances of colorectal cancer. High-risk patients will need to be screened more often," she said.

Not all risk factors for colon cancer can be changed, however. A family history of colon cancer or colon polyps (growths inside the digestive system) can increase your own risk of colon cancer.

Black people are also at higher risk of colon cancer, although experts aren't entirely sure why. A 2020 study found Black Americans were significantly more likely to die of colon cancer because they were less likely to get life-saving treatments than white peers.

Because of genetic and other factors, you can get colon cancer even if you have a healthy lifestyle, so it's still important to be aware of your risk and get screened regularly, according to Davis.

"We have met many patients, especially early-age onset colorectal cancer patients , who followed the lifestyle recommendations for cancer prevention, and they were still diagnosed with colorectal cancer," she said. "Lifestyle changes are important, but they do not replace screening."