• Drinking alcohol, having obesity, following a poor diet, and not getting enough exercise can all increase the risk of colon cancer.
• Many Americans aren’t aware that these lifestyle habits can increase their risk of colon cancer, a new survey shows.
• This lack of awareness could be contributing to rising rates of colon cancer among young people, experts say.

Many Americans don’t know that certain lifestyle factors—such as alcohol consumption and lack of exercise—can increase the risk of colorectal cancer, according to a new survey from The Ohio State University Comprehensive Cancer Center.

The survey results reflect a general lack of awareness specialists see when they speak to their patients about colon cancer risk factors, experts said.

“We talk about risk factors as if they’re immutable, but so many of them are changeable with proper education,” Matthew Grossman, MD, an interventional endoscopist and gastroenterologist at the Atlantic Digestive Health Institute in New Jersey, told Health.

That many people don’t know the risk factors for colorectal cancer (cancer of the colon or rectum, but most commonly called colon cancer) could be one reason cases of the disease are on the rise.

“It is most concerning because many of these factors are in our control,” Suneel Kamath, MD, a gastrointestinal oncologist at Cleveland Clinic, told Health. “The main takeaway [from this survey] is that many colon cancers diagnosed in the United States are preventable.”

The survey found lack of awareness was highest among Black and Hispanic people, which could mean a higher incidence of colon cancer for these populations. “Lack of awareness likely contributes to the higher number of people in the Black and Hispanic communities who get colon cancer,” Kamath said.

Below, experts explain which risk factors for colon cancer are modifiable, who may need to start colon cancer screenings early, and how awareness of risk factors might be increased.

Four Habits That Can Increase Your Risk of Colon Cancer

The new survey asked about 1,000 adults in the U.S. what they knew about the risk factors for colon cancer. The data was collected by a platform that conducts national probability-based surveys; 976 participants responded via the internet and 30 responded via phone. The data was collected in early February 2024.

It’s well known that four lifestyle habits (alcohol use, lack of exercise, having obesity, and eating poorly) can influence colon cancer risk, said Kamath. But the new survey identified gaps in knowledge among the general public.

Just over half of survey participants (51%) said they did not associate alcohol use with colon cancer. Meanwhile, 42% of people said they didn’t associate lack of exercise with colon cancer, 38% didn’t think obesity had a link to colon cancer, and 37% said poor diet isn’t associated with colon cancer.

All of these lifestyle habits have been linked to other types of cancer, as well. Alcohol alone is a risk factor for several types of cancers, including breast cancer, esophageal cancer, and liver cancer, among others. The Department of Health and Human Services’ National Toxicology Program also lists alcohol consumption as a known human carcinogen.

Similarly, eating unhealthy foods and drinks (think: sugar-sweetened beverages and ultra-processed foods) and not getting enough exercise can lead to weight gain and obesity, which can put people at risk of numerous other cancers, including uterine cancer and breast cancer. Red and processed meats, in particular, are linked to colon cancer.

Awareness and Rising Rates of Colon Cancer

Lack of awareness of risk factors could “absolutely” be tied to rising rates of the illness, particularly among young people, said Kamath. Colorectal cancer is the third most common type of cancer in the U.S., and early-onset cases have been on the rise since the mid-1990s.

Among people diagnosed with advanced-stage colorectal cancer, 11% were under age 55 in 1995; by 2019, 20% of people in this category were under age 55. In addition to a lack of awareness of risk factors, that young people aren’t routinely screened for the illness and that they may be less likely to get checked out if they notice warning signs could be contributing to the rise in cases in their age group.

“[There is] a new epidemic of young people being identified with colon cancer,” Grossman said. “People should think about [the risk factors] while they’re young.”

Hispanic and Black Americans may also be disproportionately affected by colon cancer due to lack of awareness: Black Americans are more likely to die from the illness, and cases are rising fastest among Hispanic Americans compared to any other racial or ethnic group.

Warning Signs of Colon Cancer You Shouldn’t Ignore

Given that colon cancer is being detected more frequently in younger groups, the recommended age to begin getting colonoscopies—the gold standard for colon cancer screening—was recently brought down from 50 to 45.

But some people may need to be screened earlier. If colon cancer runs your family—or even if polyps were found during your parents’ or siblings’ colonoscopies—you should speak with your physician about getting a colonoscopy earlier than recommended, said Grossman.

Similarly, if you have other risk factors like inflammatory bowel disease (IBD) or certain genetic syndromes (familial adenomatous polyposis or hereditary non-polyposis colorectal cancer, also known as Lynch syndrome), you should also get screened earlier and more frequently.

Aside from risk factors, any of the following warning signs of colon cancer should prompt a discussion with your doctor, said Grossman.

• A change in your bowel habits
• Blood in the stool
• Diarrhea or constipation
• Feeling that your bowel is not emptying all the way when you use the bathroom
• Abdominal pain, aches, or cramps
• Unexplained weight loss

The new survey underscores the need for educational movements that can help people learn the risk factors and warning signs of this disease. “Advocacy campaigns, both from the government and nonprofit groups, can be very effective for raising awareness about colon cancer risk factors,” said Kamath.

Simply put, knowing about these modifiable risk factors could save lives. “We have an excellent opportunity to educate the public that alcohol, obesity, overweight, poor diet, and physical inactivity all increase the risk of colon cancer,” said Kamath. “We could prevent many colon cancer diagnoses.”