Just as diet can have a positive or negative impact on heart, brain and bone health, your colon's overall health can be affected by what you eat.
The colon is a crucial part of the digestive system, and many different conditions can cause it to work improperly. Some of these include inflammatory bowel diseases, such as ulcerative colitis and Crohn's disease; diverticular disease; irritable bowel syndrome; and colorectal cancer.
Treatment for these conditions includes diet and lifestyle modifications, medications and/or surgery.
Colorectal cancer is one of the most serious colon diseases. Risk factors for colon cancer include age (risk increases over age 45); race (Blacks have the highest rates of colorectal cancer in the U.S.); family history; previous polyps; inflammatory bowel disease; smoking; physical inactivity; and heavy alcohol use.
"There is also a strong correlation between obesity and having a higher risk of getting cancer in the colon," says Lisa Ravindra, MD, an internist and lifestyle medicine specialist at RUSH University Medical Center.
A weighty connection
According to the National Cancer Institute, the association between obesity and increased colon cancer risk may be due to multiple factors, including increased levels of insulin in the blood, a condition that may occur more often in obese individuals. Increases in insulin and associated conditions such as insulin resistance may promote the development of certain tumors, including those in the colon.
The American Cancer Society reports that the links between diet, weight, exercise and colorectal cancer risk are some of the strongest for any type of cancer. In fact, an estimated 50% to 75% of colorectal cancers can be prevented through lifestyle changes like healthy eating, according to the Colon Cancer Foundation. So good nutrition is an important aspect of good colon health.
But it’s not all about the number on the scale. Healthy food choices and physical activity can provide a benefit even if you don’t actually lose weight.
Diet dos and don'ts
Diets high in vegetables, fruits and whole grains and low in red and processed meats have been associated with a decreased risk of colon cancer, according to the ACS. To help promote good colon health, follow these five diet recommendations:
1. Add plant-based foods into your diet.
First and foremost, eat a diet rich in whole grains, vegetables, fruits, nuts, seeds, beans and lentils. A plant-based diet does not mean eating only plants, but at least half of your plate should be plant foods, which provide many beneficial vitamins, minerals and antioxidants, and are packed with fiber — our natural cancer-fighting compounds.
It's important to eat a variety of different colored fruits and vegetables. Each plant pigment provides different nutrients or phytochemicals that offer a variety of different health benefits such as strengthened immune systems and reduced inflammation, Dr. Ravindra says.
2. Limit red meat consumption.
According to the ACS, the risk of colon cancer increases by 15% to 20% if you consume 100 grams of red meat (the equivalent of a small hamburger) or 50 grams (equivalent of one hot dog) of processed meats, like sausage, bacon or hot dogs, per day.
Prioritize chicken, turkey and fish over beef, pork and lamb. According to the American Institute of Cancer Research, eating greater than 18 ounces of red meat per week may increase your risk of cancer. If you choose to eat red meat, consume no more than 12 to 18 ounces of red meat per week.
The way you cook your red meat can also add to your risk. Try to limit cooking red meats at very high temperatures that cause charring. This causes the meat to form chemicals called heterocyclic amines and polycyclic aromatic hydrocarbons, which are linked to increased cancer risk.
3. Hold the sugar.
While sugar has not been directly associated with the progression of colon cancer, foods high in sugar are often high in calories and can lead to weight gain and obesity.
Limit added sugar to less than 25 grams a day. “The Food and Drug Administration now requires added sugars to be reported on every nutrition label. Identifying added sugars in products is easier now than it has ever been,” Dr. Ravindra says. Naturally occurring sugars in fruit are OK and can provide beneficial vitamins and minerals.
With beverages, look for sugar-free alternatives like sparkling water and unsweetened teas or coffees.
4. Up your fiber intake.
Eating a high-fiber diet is good for overall intestinal and colon health.
The American Institute for Cancer Research and ACS recommend aiming for at least 30 grams of fiber from food sources each day. Focus on incorporating a variety of whole grains, colorful fruits and vegetables, nuts, seeds and beans into your diet.
“The majority of people living in the United States do not meet their daily fiber needs,” Dr. Ravindra says. If you can’t meet your needs with fiber foods alone, a fiber supplement like Metamucil or Benfiber can be a helpful tool to reach your fiber goal.
Fiber aids colon health by helping to keep you regular and prevent constipation by moving foods through your gastrointestinal tract. This may then lower your risk of developing hemorrhoids and small pouches in your colon that can lead to diverticular disease.
5. Choose grains wisely.
Whole grains are grain products that have not been stripped of their nutrient and fiber-packed exterior. The Dietary Guidelines for Americans recommend that all adults eat at least half of their daily grains as whole grains, about three to five servings.
Some readily available whole grains include barley, quinoa, whole wheat flour, wild and brown rice and oatmeal. These foods contain more colon-friendly vitamins, minerals, fiber, essential fatty acids, antioxidants, and phytochemicals (natural compounds in plants that have a beneficial effect on the body) than their refined grain counterparts, such as white flour and white rice.
An easy way to determine if the food is a whole grain is to check the label. If the first ingredient on a grain product says "enriched," it is not a whole grain.
6. Diversify your gut microbiome.
A healthy colon contains billions or even trillions of beneficial bacteria per milliliter. A diet containing a variety of nutrient-dense food types, fiber-containing foods and probiotic food sources helps to shape a colon’s microbiota.
“A plant-based or Mediterranean-style eating pattern has been shown to diversify the gut microbiota as well as reduce the risk of developing colorectal cancer,” Dr. Ravindra says. Foods containing probiotics can also help to foster growth of the gut flora in the colon. Those looking to increase their intake of probiotics may try foods such as yogurt, kimchi, kombucha, tempeh, kefir, miso and sauerkraut.
Make screening a priority
While eating right can help keep your colon happy, the most powerful way to prevent colon cancer is through screening. A colonoscopy is an examination of the colon that allows physicians to both screen for and prevent colorectal cancer.
"Colonoscopy reduces the risk of developing colon cancer because precancerous polyps can be detected during the test and removed," Dr. Ravindra says. "This test is unique to most screening tests because it can actually look for precancerous growths and remove them during the procedure, which ultimately reduces a person’s risk of developing colon cancer."
If detected early, up to 95% of colorectal cancers are curable, according to the Colon Cancer Foundation. "Colon cancer is a largely treatable condition," Dr. Ravindra says. "For colorectal cancer, we have a test, it is not complicated and it is extremely effective in preventing it and catching it early.”