The Impact of Diet and Lifestyle on Colon Cancer Risk

Colorectal cancer is one of the most common but preventable types of cancer.  The American Cancer Society estimates 106,590 new cases of colon cancer  and 46,220 new cases of rectal cancer in the United States in 2024. Simple changes to your diet and lifestyle can play a significant role in colorectal cancer risk.  

V. Karlos Arcos, M.D., is a board-certified colorectal surgeon with INTEGRIS Health Baptist Medical Center. Below, he shares information about the link between diet and colorectal cancer risk.

Red meat and colon cancer

The big picture: Red meat itself, along with the way it's cooked, increases the risk of colon cancer in people who consume it regularly. Researchers have found a specific pattern of damaged DNA in people with colorectal cancer who also consumed red meat regularly. 

• Heme iron, the form of iron in red and processed meat, when broken down in the digestive tract can form harmful substances called nitroso compounds.  These can damage our DNA and might cause cancer in the bowels. 
• Cooking red meat at high temperatures creates substances called heterocyclic amines and polycyclic aromatic hydrocarbons, which are associated with colorectal cancer. 
• Red meat contains several types of saturated fat, including myristic, palmitic and stearic acids, which can increase the risk of colon cancer. 
• Because of these risks, the American Institute for Cancer Research recommends eating no more than 18 ounces of cooked red meat per week. 

Categorizing these meats:

• Examples of red meat include beef, lamb, pork, veal, venison and goat. 
• Processed meats include any smoked, cured or salted meats. Examples include deli meats, bacon, hot dogs, sausage, pepperoni and beef jerky. 

What the numbers say: The International Agency for Research on Cancer (IARC), an organization that evaluates the causes of cancer, examined the impact of eating red meat and processed meat. 

• Eating just 50 grams of processed meat every day could increase the risk of colorectal cancer by around 18 percent, according to a study of 10 research projects. 
• Eating 100 grams of red meat every day could increase the risk of colorectal cancer by 17 percent, according to that same research. 

Other foods with colorectal cancer risk 

In addition to red meat and processed meat, there are other foods to avoid that can increase your risk of colon cancer. 

• Sugary foods can lead to inflammation and insulin resistance, potentially promoting the growth of cancer cells. 
• Foods high in saturated fat can change gut bacteria, raise cholesterol and cause inflammation, all contributing to a higher risk of colon cancer. 
• Soda or other sugary carbonated drinks - consuming two sugar-sweetened drinks a day had more than double the colorectal cancer risk in women, according to a study from 2021. 

Dietary changes to reduce colon cancer risk

• A diet rich in fruits and vegetables provides antioxidants, anti-inflammatory properties, fiber and other nutrients that are beneficial for gut health. 
• Swap refined grains for whole grains such brown rice, whole wheat pasta or whole grain bread. These high-fiber foods help promote colon health. 
• Low-fat dairy products, such as reduced fat milk, yogurt and cheese, are lower in saturated fat and less likely to increase the risk of colon cancer. Dairy products also contain calcium – not getting enough calcium in your diet has been connected to a higher chance of developing colon cancer. 
• Incorporating lean protein sources, such as chicken, turkey, seafood and beans, offer protein without adding high amounts of saturated fat to your diet. 

"A high fiber diet with minimal red meat and processed foods, daily exercise, and avoiding tobacco and alcohol can significantly improve your risk of colorectal cancer, as well as your health overall," Arcos says.

Exercise and colon cancer

Why it matters: In general, a sedentary lifestyle increases the risk of any type of cancer. Seven and a half hours of moderate physical activity per week can lower the colon cancer risk in men by 8 percent, while 15 hours per week can lower the risk by 14 percent, according to a 2020 study. 

• Regular physical activity keeps certain hormone levels in check. High hormone levels can increase your cancer risk. 
• Being active helps control insulin levels and avoids insulin resistance, a condition that can create excess inflammation and increase your cancer risk. 
• Physical activity helps improve the transit time of food in the gastrointestinal tract, meaning foods that may contain potential carcinogens (cancer-causing substances) spend less time in the colon. 
• Not exercising can cause weight gain, and carrying extra weight can increase estrogen and insulin production (hormones that can fuel cancer growth). 

Alcohol consumption and colon cancer

The lowdown: Alcohol consumption has been linked to an increased risk of colon cancer. A recent 2023 study in Korea found moderate to heavy drinking caused a 47% increase in colon cancer among women and a 26% increase in colon cancer among men. 

Acetaldehyde, a toxic byproduct of alcohol metabolism, can have harmful effects on the mucosa of the colon, including promoting excessive cell growth that leads to cancer. 

Alcohol consumption can create oxidative stress in cells, which makes them more susceptible to damage that heightens the risk of cancer. 

Drinking alcohol can decrease absorption of nutrients, like folate. Low folate levels are a risk factor for breast and colon cancer. 

Next steps: Regular exercise, a healthy high fiber diet, lowering the intake of red meat and processed meat and limiting alcohol are the easiest ways to decrease colon cancer risk. To schedule a colonoscopy today, talk to your primary care provider or visit our colorectal cancer page.