Diet, Obesity, and Colon Cancer: Learn the Risks

  • Lifestyle factors can have a major impact on the risk of colon cancer. This might not seem like news, but consider the big picture. According to the American Institute for Cancer Research (AICR), colorectal cancer is the third most common cancer in the United States. So, any way we can reduce that risk is valuable.

    “Close to 50% of colorectal cancers could be prevented with a healthy lifestyle,” said Rishi Jain, MD, MS, DABOM, a medical oncologist at Fox Chase Cancer Center. “That includes physical activity, diet, and obesity management.”

    Cutting the risk of any cancer by half is no small feat. Here’s how lifestyle and colon cancer are connected.

    The link between obesity and colon cancer

    Excess weight increases insulin and related hormones in the blood. These can encourage cancer growth. Plus, excess fat can create an environment that is friendly for inflammation. This can also contribute to the growth of cancer.

    Those are the basics. But researchers are still figuring out why people who are considered obese may have a higher risk of developing and dying from colon cancer. It’s possible that overweight patients may not get enough chemotherapy if the dose for the drug is based on weight. Or other conditions common in people who are overweight adults—like diabetes or lung disease—may complicate cancer treatment. It’s also possible that tumor biology is more complex in people who are overweight.

    How diet affects colon cancer risk

    Red meat and processed meats like hot dogs and bacon have been linked to increased colon cancer risk. Drinking two or more alcoholic drinks a day can increase risk as well.

    Fortunately, other foods have been shown to lower the risk. Eating whole grains—like those in brown rice or whole-wheat bread—can reduce risk. So can adding more vegetables, fruits, and beans to your diet. Consuming foods high in Vitamin C can help, too.

    “It isn’t just one specific food or nutrient that contributes to risk,” Jain explained. “It’s the overall dietary pattern. On the whole, are you consuming more whole foods or more processed carbs and meats?”

    What you can do to reduce your risk

    Small changes can make an impact. And any way you can reduce colon cancer risk is worthwhile.

    You can cut your risk by getting regular exercise and watching your weight. A diet of vegetables, fruits, and whole grains helps, as does limiting red meat, processed meat, and alcohol.

    Talk to your doctor about regular screening with a colonoscopy or stool-based testing. Polyps that form in the colon may become cancerous if left in place. Screening can find polyps so they can be removed before they turn into cancer. The American Cancer Society recommends testing for colon cancer starting at age 45, but that guidance may change based on your personal risk for the disease. Work with your care team to come up with a screening plan that’s right for you.

    For more information on cancer risk, Jain recommends AICR’s website. There, you’ll find the latest research about lifestyle factors and how you can lower your risk for colon cancer and other cancers.