Good nutrition is important for good health — especially during treatment for colorectal cancer.
"Many patients wonder what they can do to make their treatment more effective," says Dr. Anaum Maqsood, a gastrointestinal medical oncologist at Houston Methodist Hospital. "I encourage them to eat a healthy diet because that can help them feel better, maintain their strength, support their immune system and recover faster."
Food plays an important role in fortifying the body after colon cancer surgery and during treatment such as radiation, chemotherapy and immunotherapy, but eating well — as well as staying hydrated — can be a challenge due to treatment side effects such as:
- Decreased appetite
- Nausea and vomiting
- Weight loss
- Diarrhea
- Constipation
- Sores in the mouth or throat
- Dry mouth
- Trouble swallowing
- Changes in the way food tastes
However, you won't be alone in managing your diet. Clinical dietitians at Houston Methodist Neal Cancer Center are specially trained to support the nutritional needs of people with cancer. They can personalize a nutrition plan to your needs, preferences and treatment to support healing through colon cancer treatment.
Foods and drinks to avoid
Some colon cancer treatments can weaken your immune system, making it more difficult to recover from foodborne infections. So be especially diligent when handling and preparing food. While these foods don't directly cause colon cancer, they can cause foodborne illness:
- Raw fish and shellfish
- Soft-cooked or raw eggs
- Unwashed fruits and vegetables
- Unpasteurized cheeses and dairy products
Consuming sugar and fiber, however, is confusing for patients, says Dr. Maqsood.
"Many patients believe that depriving the body of all sugars can kill cancer, but this is not true," says Dr. Maqsood. "It can lead to starvation of the body. While you should limit food with added sugar, such as soda or candy, there are good sugars like what is found in fruit that are nutritious and produce the right kind of energy. You need healthy sugars for your body to be able to withstand the stress of the cancer and treatment."
Fiber is key to a healthy diet — it helps reduce inflammation and promotes the growth of healthy gut bacteria. But during treatment, eating too much fiber can worsen digestive symptoms associated with treatment. The same goes for saturated and unsaturated fats, which can contribute to stomach upset and loose stools.
Grapefruit and some vitamins and herbal supplements can reduce the effectiveness of certain treatments. Check with your care team about specific foods and supplements to avoid.
Good foods and drinks during treatment
"If you have cancer, you may need extra calories and proteins to help you keep up your strength," says Dr. Maqsood. "Sometimes we ask patients to try different food combinations to settle on what is most acceptable to their digestive system."
Talk with your health care team about what foods may be best during treatment. In general, foods that you should add to your diet during colon cancer treatment include:
- Protein-rich foods – chicken, fish, beans, legumes, tofu, dairy
- Healthy fats – olive oil, grapeseed oil, avocado
- Nutrient-rich carbohydrates – whole grain bread and pasta, brown rice, quinoa, bran, oats
- Vitamins and minerals – milk, fruits, vegetables, yogurt
It's also important to drink plenty of water to help reduce the gastrointestinal (GI) side effects of treatment. You may need to drink electrolyte beverages if you have diarrhea or vomiting.
If you have symptoms such as loss of appetite, here are a few tips that may help:
- Eat smaller meals and snacks five to six times a day
- Eat when you're hungry, no matter the time
- Eat foods that smell good
- Eat high-protein foods first during your meal
- Try new foods and recipes
- Take most of your fluids between meals so you don't feel too full while eating
- Drink lots of water, along with high-calorie, high-protein beverages or nutrition supplements such as Ensure or Boost
- Sip milkshakes, smoothies or soup if you do not feel like eating solid foods
Nutrition tips for life after treatment
Once you've finished your treatment, continue a healthy diet to help prevent the risk of colon cancer recurrence. Along with impacting your colon and rectal health, a nutritious diet also helps maintain a healthy body weight, which has been shown to reduce cancer risk. In fact, people with obesity are 1.3 times more likely to develop colorectal cancer.
Foods to help maintain good colon health include:
- Dairy
- Lean proteins, such as chicken, fish, beans, lentils, tofu, quinoa and chickpeas
- Olive oil
- Whole grains and beans
- Vegetables and fruits
Foods to avoid (or consume less of) include:
- Alcohol
- Processed meats such as lunch meat, sausages and hot dogs
- Red meat
- Sugary sweets and beverages
Houston Methodist is dedicated to conducting clinical trials to help find better treatments for colon cancer.
"We have two clinical trials at Houston Methodist looking at the effects of certain foods and diets used during specific colon cancer treatments," says Dr. Maqsood.
One is examining whether using olive oil supplements can modify the antioxidant environment in the colon for a better treatment response. The other trial pairs a keto diet with immunotherapy to understand whether fats help the medication work better in a tumor microenvironment.
There is no one perfect diet when it comes to healing from colon cancer. Every person will have different dietary symptoms and side effects during treatment. Don't hesitate to ask questions or raise concerns and challenges to eating with your health care team. They are ready to help you find the healthy, balanced diet necessary to help you fight colon cancer.
