Keep your colon healthy through diet and cancer screening

Friday, March 21, 2025

[5 MIN READ]

Your colon plays an important role in the digestive process by moving food waste into the rectum, which passes it out of the body.
An imbalance in gut bacteria can contribute to both physical and mental health issues.
You can lower your risk factors for colon cancer by limiting red meat and processed meat, eating more fiber and undergoing colon cancer screening.

Keep your colon healthy through diet and cancer screening

You could think of the colon as the unsung hero of the body. While the rest of the organs (the heart and lungs, for example) get all the attention, the colon quietly does its job of helping food pass from the digestive system and out of the body. It has an all-important function — which means that if it isn’t working correctly, your body won’t, either.

How the colon works

When you chew and swallow food, you break it down into smaller pieces so it can start its journey through the esophagus and into the stomach. In the stomach, it becomes liquid and is passed into the small bowel, also called the small intestine. The small bowel continues to process the food and helps your body absorb all the important vitamins and minerals.

Then, after the now-liquid food passes into the colon, the water becomes absorbed, and bacteria in the colon break down the remaining material. Your colon moves the waste into the rectum, which passes it out of the anus in the form of stool.

When your colon isn’t healthy, you may have trouble eliminating waste, which could cause bloating, constipation, pain and diarrhea. Plus, according to Elizabeth Broussard, M.D., a Providence gastroenterologist who treats patients in Seattle, Washington, additional problems could occur.

“There is emerging evidence about the ‘gut-brain axis,’ which is a two-way highway between the brain and the gut,” she says. “They influence each other, affecting both mental and physical health. There are trillions of bacteria in the gut, and they produce neurotransmitters that can impact brain function and mood regulation. Imbalance in gut bacteria can contribute to mental health issues like anxiety, depression and cognitive decline.”

Enrich your diet with fiber

Adequate fiber intake is essential for a healthy colon. “Fiber helps the digestive system move smoothly, preventing constipation and supporting a healthy microbiome,” says Dr. Broussard.

Every day, adult women should consume 25 grams (g), and men should have 38g of fiber. To reach your target, try to incorporate fiber-rich foods, including:

Fruit, such as avocado (10g/cup), raspberries (8g/cup), pears (6g/cup), apples (4g/cup) and bananas (3g/medium banana)
Veggies, such as Brussels sprouts (4g/cup), carrots (3.5g/cup) and broccoli (2.5g/cup)
Legumes, including lentils (15g/cup), chickpeas (12.5g/cup) and kidney beans (11g/cup)
Whole grains, including oats (16g/cup), quinoa (5.2g/cup) and brown rice (3.5g/cup)

Keep track of your fiber intake for a while to see how you’re doing — reading food labels can help. Begin by replacing processed foods, such as white bread and rice, with whole-grain products. Then add fiber in the form of fruit, vegetables or legumes. Increase by just one serving at a time and then wait a few days before adding more. This can help prevent uncomfortable side effects, such as gas and diarrhea.

Limit red meat and processed meat

The American Cancer Society has long recommended a diet that limits processed meat and red meat. Experts note that:

Eating 50 grams (about four strips of bacon or one hot dog) of processed meat every day increased the risk of colorectal cancer by 18%.
For red meat, there was evidence of an increased risk of colorectal, pancreatic and prostate cancer.

“Instead of red meat, you should opt for turkey, chicken and plant-based protein like beans, tofu and tempeh,” says Dr. Broussard. “Not only will those other sources of protein help your colon, but they are also good for heart health, as well.”

Stay away from added sugars

Foods that are high in sugar can lead to obesity, which in turn can cause problems with the colon.

The solution for many people is to limit sugar intake to 25 grams or less each day. This doesn’t include naturally occurring sugars, such as those found in fruits. Many people have found that lowering their sugar intake and increasing the amount of fiber they consume helps significantly with their gut health.

Additionally, says Dr. Broussard, you should avoid excessive alcohol and caffeine. Women should stick to no more than one drink of alcohol daily, and men should have no more than two drinks.

Get screened for colon cancer

Besides keeping an eye on your diet and alcohol and caffeine intake, you should also participate in regular cardiovascular exercise and get screened for colon cancer.

“A colonoscopy is the gold standard for colon cancer screening,” says Dr. Broussard. “Colon cancer is a preventable cancer, unlike most other common cancers. Mammography allows for early detection, but not prevention, of breast cancer. Chest CT (computed tomography) allows for early detection, but not prevention, of lung cancer. A colonoscopy can prevent colon cancer, which develops from precancerous growths called polyps. If polyps are removed during colonoscopy, then cancer cannot develop. Polyps do not cause pain, and you cannot feel them growing. There is no way to find or remove polyps except for colonoscopy.”

You may have heard about a fecal immunochemical test (FIT), which is a stool test that looks for blood in the colon. The source of that blood can be colon cancer that has already developed, or a large colon polyp that has grown over time. “FIT does not test for colon polyps,” cautions Dr. Broussard. “This is why we recommend colonoscopy over FIT for prevention of colon cancer.”

By watching what you eat and knowing the current colorectal cancer screening guidelines, you can make sure your colon is fit and healthy to do the work it was always meant to accomplish.

Contributing caregiver

Elizabeth Broussard, M.D., is a Providence gastroenterologist who treats patients in Seattle, Washington.

Find a doctor

If you’re concerned about your colon health, talk to your doctor. A Providence dietitian can help you develop a diet and make food choices that are rich in nutrients and fiber to help you maintain a healthy colon. You can find one in our provider directory. Through Providence Express Care Virtual, you can also access a full range of health care services.

Download the Providence app

It’s all in the app: easily stay connected with Providence and your health. With the Providence app, you can schedule appointments, have virtual visits from the comfort of your own home, get health recommendations personalized for you, access your health records and so much more. Learn more and download the app.