What to Eat to Prevent Colon Cancer

Salmon, kale, pumpkin and grains

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Although scientific studies seem conflicting on what you should and shouldn't eat for colon cancer prevention, there is one constant: A diet rich in fruits and vegetables is good for you. There is no such thing as a cancer prevention diet, but there are things you can eat to reduce your personal risk of developing colon cancer, even if you have a strong family history of the disease.


Tips For Preventing Colon Cancer

What Is a Healthy Diet?

The term "healthy diet" is subjective. To some people, it may mean ordering a smaller diet drink or adding a spinach salad to their fried chicken. The fact is, a healthy diet is a well-balanced diet that incorporates more than food selections—the cooking and preservation methods may impact your cancer risk, too.

Building Your Plate

Regardless of what meal you are about to consume (breakfast, lunch or dinner), your plate should be heavy on the fruits and vegetables, light on the animal proteins and fats. The American Cancer Society's guidelines suggest eating at least two-and-one-half cups of fruits and vegetables (that's combined servings) daily to decrease your risk of cancer. If you fill your plate full of fruits or vegetables, you will have less room for the fats and animal proteins.

Altering Lifestyle to Mirror the Healthy Diet

If you smoke or drink alcohol, your body may require more nutrients than a non-smoker or non-drinker. Studies show that smoking can deplete your body of vitamin C, which is a potent antioxidant. Antioxidants help reduce your colon cancer risk by sweeping out the free radicals (pollution, cellular waste) in your body. Heavy alcohol use can deplete the amount of folate (one of the B vitamins) that you absorb from healthy foods. Folate deficiency has been linked to an increased instance of colon cancer.

Eat the Real Deal

You can find almost every micronutrient (think minerals, vitamins) available in a pill form nowadays. However, it's not just the micronutrients in healthy foods that matter. It’s the synergy of nutrients, phytochemicals, and antioxidants — basically, the food as a whole — that helps fight cancer cells.​

A number of scientific studies and trials have demonstrated that taking large quantities of supplements, such as beta-carotene or calcium, in an effort to combat cancer risk can be counterproductive. Some of these trials, especially those containing beta carotene, showed an increased risk of developing cancer while taking these man-made supplements.

The safest and most economic way to get all of your antioxidants, phytochemicals, and nutrients is by eating the whole, natural, plant-based food — largely unchanged from when it was harvested. Wash the vegetables and fruits thoroughly, and enjoy the skins that are edible as well — this is where the fiber is stashed.

Mix It Up

Get the most benefit out of your diet by incorporating a healthy variety of foods. Try to avoid eating the same fruits, vegetables, and grains repeatedly. Each type (and color) of healthy food has its own micronutrients that are specific to that food group.

  • Green leafy vegetables, such as kale, spinach, and broccoli, are full of natural lutein, vitamin E, beta-carotene and calcium
  • Orange fruits and vegetables, such as carrots, cantaloupes, and pumpkin, contain natural beta carotene
  • Tomatoes, watermelon, and pink grapefruit contain lycopene
  • Almonds, mangoes and safflower oils contain natural vitamin E
  • Fish, oranges, cereals, poultry, and many other foods contain vitamin C
  • Rice, wheat, and Brazil nuts are a healthy source of selenium

You cannot overdose on micronutrients, antioxidants, and minerals by eating them in their natural food state. Try adding one or two fruits or vegetables to your meals at a time, making healthy foods a permanent part of your diet.

Cooking Methods

When you cook meat over high temperatures (think broiling, grilling, and frying), compounds are released into the meat. The two compounds released are polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs). They have known carcinogens and have been linked to an increased incidence of colon and rectal cancers. PAHs can also be found in cured or smoked foods, such as ham or bacon.

You don't have to toss your backyard grill, but it may be healthier to slow-cook foods at lower temperatures, stew, or slowly roast animal proteins.

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. ACS Guidelines on Nutrition and Physical Activity for Cancer Prevention. American Cancer Society.

  2. It’s Easy to Add Fruits and Vegetables to Your Diet. American Cancer Society. 2017.

  3. Ahmadi-motamayel F, Falsafi P, Goodarzi MT, Poorolajal J. Evaluation of salivary catalase, vitamin C, and alpha-amylase in smokers and non-smokers: a retrospective cohort study. J Oral Pathol Med. 2017;46(5):377-380.  doi:10.1111/jop.12495

  4. Kapinova A, Kubatka P, Golubnitschaja O, et al. Dietary phytochemicals in breast cancer research: anticancer effects and potential utility for effective chemoprevention. Environ Health Prev Med. 2018;23(1):36.  doi:10.1186/s12199-018-0724-1

  5. Antioxidants: In Depth. National Institutes of Health. November 2013.

  6. FoodData Central. US Food & Drug Administration.

  7. Wang H, Yamamoto JF, Caberto C, et al. Genetic variation in the bioactivation pathway for polycyclic hydrocarbons and heterocyclic amines in relation to risk of colorectal neoplasia. Carcinogenesis. 2011;32(2):203-9.  doi:10.1093/carcin/bgq237

Additional Reading
  • Sinha, R., Peters, U., Cross, A.J., et al. (September 2011). Meat Cooking Methods and Preservation and Risk for Colorectal Adenoma.Cancer Research, 65; 8034. 

  • Willet, W.C. (2010). Fruits, Vegetables, and Cancer Prevention: Turmoil in the Produce Section. Journal of the National Cancer Institute: 102 (8).

  • American Cancer Society. (2006). American Cancer Society's Complete Guide to Colorectal Cancer. Clifton Fields, NE: American Cancer Society.
  • American Cancer Society. (n.d.). Common Questions About Diet and Cancer. ACS Guidelines on Nutrition and Physical Activity for Cancer Prevention.
  • National Cancer Institute. (n.d.). Antioxidants and Cancer Prevention: Fact Sheet

By Julie Wilkinson, BSN, RN
Julie Wilkinson is a registered nurse and book author who has worked in both palliative care and critical care.