From the inside out: The role of your gut in cancer

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From the inside out:
The role of your gut in cancer

5 min read

Have you ever considered what actually happens to food after it passes your lips? Why do certain foods make us feel energetic, sluggish or upset our stomachs? Science can help explain how your digestive system, and more specifically, your gastrointestinal (GI) tract, is much more than a tube that food passes through. It plays an important role in your overall wellness.

Your GI tract plays a specific role in breaking down food, gathering nutrients and eliminating waste in your body. This process uses nerves and hormones to make sure the job gets done correctly.

Your GI tract is also home to trillions of bacteria that help process foods and maintain a state of balance and overall well-being for your body. The key to this balance is thought to be in the “microbiome.” The microbiome is made up of bacteria and other microorganisms in your stomach and intestines, or what we like to call your “gut.” Inside your gut, your body works with the microbiome to maintain balance against a regularly changing environment.

Your gut is thought to be connected to your brain through a large nerve called the vagus nerve. The physical and chemical connections between your gut and your brain, also known as the “gut-brain axis,” are guided by millions of nerves and neurons. That’s why your gut may also affect how your brain functions.

How does cancer impact your gut?
Common cancer treatments like chemotherapy may cause GI side effects such as diarrhea or nausea. Because chemotherapy targets fast growing cells, such as cancer cells, healthy cells may also be damaged in the process. In addition, common medicines such as antibiotics may be harmful to both the good and bad bacteria of your microbiome.

Strategies to improve your gut health
Factors such as stress and poor diet may also contribute to gut imbalances. Improving your gut health is a complex process, but there are changes you can make to help it along.

Sami Mansfield, founder of Cancer Wellness for Life, shares a few tips to help improve your gut health.

  1. Add good bacteria. Eat fermented or probiotic foods such as yogurt, kefir, kombucha or sauerkraut. These can help your gut get good bacteria. You can buy these products at the store or make them at home. Make sure to talk to your doctor before consuming products with live cultures or probiotics.
  2. Bulk up on fiber. Fiber helps keep the gut healthy and regular. Fruits and vegetables are great sources of high fiber. Black or kidney beans have lots of fiber and can easily be added into meals. Seeds, such as chia seeds, also have a high fiber content and can be made into overnight pudding or added on top of fruit and yogurt.
  3. Get a move on. Research has shown that people who are less active have a less diverse microbiome. Start with small amounts of movement each day and focus on adding more days of exercise instead of longer sessions.
  4. Take time to breathe. When you are feeling stressed, so is your gut. No one can avoid stress completely, so take a minute to stop and breathe. If possible, close your eyes. Start by taking slow, deep breaths for 4 to 5 counts. Breathe through your nose, lifting your shoulders up and pause. Then exhale through your mouth for 4 to 5 counts. Press your shoulders down and back as you exhale through your mouth. Try to do this 5 times.
  5. Rest up. Everyone has a circadian rhythm or biological clock that runs on a 24/7 schedule and determines important functions in your body like digestion and sleep. If you’re not getting enough sleep, it may disturb your digestion and your microbiome. Keep a sleep regimen to help you stay on track.

All wellness strategies must be part of a lifelong process and not just a one-time event. Continue working to improve your gut health whenever you can.

The information contained herein is provided for educational purposes only and is not intended to replace discussions with a healthcare provider. All decisions about your health and nutrition should be made with a healthcare provider.


Sami Mansfield is an oncology exercise specialist and Director of Oncology Wellness for one of the largest cancer centers in the Midwest. She is also the founder of Cancer Wellness for Life, an organization focused on developing oncology wellness and exercise resources for hospital and healthcare organizations, nonprofits and individuals affected by cancer.