The foods we eat act as fuel for our bodies. They give strength and stamina to power through the day. At no time is this more important than when a person is undergoing treatment for cancer.
While lifesaving or life-preserving, chemotherapy and radiation treatments can take a toll on a person's body and significantly affect their diet.
For example, chemotherapy not only kills rapidly dividing cancer cells, but also it can destroy fast-growing healthy cells. This may cause nausea or appetite changes, leading patients to consume fewer calories than needed. Other treatments can cause uncomfortable dry mouth, diarrhea or constipation. Fortunately, these side effects can be overcome and thereby improve nutrition during treatment.
One of the things patients and caregivers ask about is weight changes during treatment. Generally, if a patient loses more than 3 pounds in one week, it's important to discover if the loss was intentional or unintentional. If it's intentional, the patient's care team will discuss why this is occurring and make sure treatment plans are going well.
If the weight loss is unintentional, it's important to seek out the cause and provide support. It's important to avoid a rapid decline in weight because muscle tissue is being broken down during treatment. This can lead to further loss of the patient's stamina.
The cause of weight loss that patients report most frequently is poor appetite. This is a common side effect during cancer treatment.
To improve nutrition during this time, it helps to plan for small, frequent meals. That can be daunting because patients and caregivers may not have the energy to make multiple meals each day.
One way to get around this is to reserve a portion of what would have been normally eaten during breakfast, lunch and dinner for a fourth small meal. This makes it easier to plan and schedule additional meals with less work.
Here are other ways that caregivers can help a loved one who is experiencing weight loss due to poor appetite:
- Gently remind the loved one to eat small, frequent meals and snacks throughout the day.
- Offer starchy foods and high-protein foods together. For example, a piece of toast and cheese stick.
- Keep cool drinks and juices within reach. Drinking between meals keeps the person hydrated while avoiding filling up on liquids during mealtimes.
- Create pleasant settings for meals and eat together. Light a candle or place the table near a window to enjoy the view.
- Choose high-calorie foods or nutrition supplement drinks.
Damage to the stomach and intestinal lining during cancer treatment can cause nausea and vomiting. Many medications are available that control nausea and provide relief.
Patients and caregivers also can do other things to ease this side effect through diet, including:
- Choose easily digestible foods, such as refined carbohydrates like white bread and potatoes. Avoid high-fiber, high protein foods, as these foods take longer to digest.
- Eat small, frequent meals to avoid overloading the stomach.
- Gradually sip clear liquids between meals, being careful not to gulp excess air.
- Avoid foods with strong smells. If needed, cook foods outdoors to minimize smells.
- Use plastic, wood or bamboo utensils.
- Take medications as prescribed.
Some cancer treatments and medications can cause dehydration and decreased saliva production. This leads to uncomfortable dry mouth.
Follow these tips to prevent sores and cavities:
- Increase fluid intake.
- Create extra saliva by chewing gum or sucking on hard candy or ice chips.
- Eat soft foods like avocado, applesauce or eggs.
- Use balm to keep lips moist.
- Suck on sugarless candy or chew sugarless gum. Avoid mentholated candy.
Dry mouth and a general decrease in saliva can change the way that foods taste. In some cases, a complete lack of taste can make foods unappealing.
If this occurs, try these tips:
- Chew gum or suck on hard candy to change the flavor in the mouth.
- Increase amount of seasoning in foods.
- Use nonmeat protein sources, like tofu, beans or lentils, if meat is unappealing.
- Use plastic, wood or bamboo utensils and dishes.
- Make foods that look and smell appealing.
Sore throat or mouth
A side effect of some chemotherapy and radiation treatments is a sore throat or mouth. This can make eating and drinking uncomfortable and painful.
Follow these tips:
- Eat foods and drinks at a moderate temperature. Very hot or cold foods can be irritating.
- Choose soft, bland foods like mashed potatoes or bananas.
- Avoid spicy or acidic foods.
- Use topical numbing cream if sores are present.
- Use a blender to smooth out foods.
- Take pain medication before mealtimes.
- Keep mouth clean and lips moist.
- Rinse mouth before and after meals with plain water.
Diarrhea and constipation
Bowel changes are unpleasant but common side effects in people receiving treatment for cancer. Diarrhea may just be an uncomfortable problem, or a sign of something more serious. Diarrhea also can lead to other problems, such as severe dehydration. Chemotherapy, pain medications, dehydration or being less active can cause constipation.
Patients should modify their diets and behaviors if they start to experience:
- Eat small, frequent meals and snacks.
- Choose soft, low-fiber foods.
- Avoid caffeine.
- Limit alcohol.
- Limit dairy products.
- Drink plenty of room temperature fluids but less with meals and more between meals.
- Take medications as prescribed. Ask your health care team before using any over-the-counter diarrhea medication.
- Avoid extremely hot meals. Hot or very warm meals can increase the speed food moves through your digestive system.
- Drink plenty of fluids, at least 64 ounces per day.
- Eat prunes or drink prune juice.
- Keep regular mealtimes.
- Increase activity.
- Use a stool softener.
It's important to do what you can to maintain calorie, protein and fluid intake during cancer treatment. Following dietary guidelines carefully helps patients maintain strength and stamina during treatment.
Keep in mind that in some cases, such as advanced cancer, eating may not affect the outcome of your illness or treatment. In these situations, trying to follow specific dietary guidelines, such as adhering to a low-sodium or low-fat diet, may not be practical.
Talk with your care team about what you can expect during treatment and how long symptoms could last. Discuss all your symptoms with your health care team, especially those that affect your diet.
Watch the annual Lloyd & Ardis Peterson Cancer Symposium to gather more diet tips and hear from author Brenda Elsagher, who offers a humorous account of her personal cancer experience:
Rose Prissel is a Mayo Clinic dietitian in Rochester, Minnesota.