Some cancer treatments can cause side effects, as can the cancer itself. Nutritious food choices can help you stay healthy and cope with side effects such as:

• Nausea and vomiting
• Diarrhea
• Constipation
• Loss of appetite
• Taste changes

Ask your care team about foods you can eat to help relieve treatment side effects, as well as foods to avoid. One of our cancer nutritionists can also provide a list of such foods. You can also take steps to minimize certain side effects:

Nausea and vomiting

• Eat small amounts, slowly and more frequently.
• Choose foods that appeal to you at that moment.
• Eat in a place that feels comfortable, avoiding stuffy environments that are too warm or are filled with cooking odors.
• Drink liquids a half hour before or after meals, but not while eating.
• Drink slowly or sip liquids throughout the day.
• Rest after you eat, but stay upright for about 1 hour after eating.
• Wait a couple of hours before eating if you feel nauseated during treatment.
• Keep a diary of when you feel nausea, how long it lasted, what you ate, and where you were. Your doctor or nurse can use the information to help you better manage your symptoms.

Diarrhea

Diarrhea may cause dehydration, excessive loss of fluid from the body, and low levels of essential minerals such as sodium and potassium. We recommend drinking 6 to 10 cups (48 to 80 oz) of fluids each day. If you have diarrhea, you may need to drink more than usual.

For sudden, short-term diarrhea, the National Cancer Institute recommends consuming only clear liquids for the next 12 to 14 hours. Clear liquids include:

• Water
• Broth or bouillon
• Fruit juices diluted with water
• Oral rehydration solutions such as DripDrop, Pedialyte, or Ceralyte
• Sports drinks such as Gatorade or Powerade

Constipation

Constipation results from hard, dry stool (feces) that is difficult to pass, resulting in less frequent bowel movements. Besides being uncomfortable, constipation can reduce your appetite. Tips to relieve constipation include:

• Drink plenty of liquids.
• Try to get more exercise.
• Eat high-fiber foods.
• Ask your care team about stool softeners or laxatives that you can take.

Loss of appetite

Some cancer treatments can cause you to lose your appetite, as can side effects such as nausea or vomiting. Fatigue and the stress of coping with cancer can also make you feel like you don’t want to eat.

Don’t wait to seek help until you are dehydrated, have lost weight, or feel weak. Talk with your care team right away if you don’t feel hungry. We may be able to prescribe medications or provide other suggestions to improve your appetite and help you maintain your strength.

Tips for maintaining nutrition include:

• If you can’t eat very much at one time, eat more frequently throughout the day.
• Frequent meals or high-protein, high-calorie snacks, even if they are small, make up for larger, less frequent meals.
• Use the clock to tell you when to eat. Try to eat something about every 3 hours.
• Keep easy-to-prepare, nutritious foods within reach so you can have something whenever you feel like it.
• Don’t forget to take a snack with you whenever you go out.
• If you don’t feel like eating regular food for a meal, try liquid meal replacements.

Taste changes

You may experience changes in the way you taste food, which can decrease your appetite and desire for food. Foods may taste bitter, metallic, or too sweet. Our recommendations include:

• Keep good oral hygiene:
  • Brush your teeth at least twice a day.
  • Rinse your mouth after you eat, using plain water or mixing in baking soda and salt.
• Add seasoning to your food to compensate for various sensation changes:
  • Metallic: Add a little sweetener, such as agave nectar or maple syrup, and a squeeze of lemon juice. Or add a fat such as a nut butter.
  • Too sweet: Add 6 drops of lemon or lime juice. Taste, then add more if you like.
  • Too salty: Add ¼ teaspoon of lemon juice.
  • Too bitter or sour: Add a little sweetener.
  • Too bland: Add sea salt and/or a squeeze of lemon juice.
  • Too spicy: Add a little sweetener or a fat such as a splash of olive oil.

Maintaining a healthy weight during treatment

Staying at a healthy weight during cancer treatment means maintaining your lean body mass. Lean body mass includes muscle, bone, and organs.

Maintaining your lean body mass may:

• Reduce your risk of complications during treatment
• Improve your response to treatment
• Help you maintain your overall health and well-being

Tips for avoiding excessive weight loss

• Eat at least 3 meals per day.
• Plan well-balanced meals that include:
  • Lean protein
  • Fruits and vegetables
  • Healthy fats
  • Complex carbohydrates
• Add high-calorie beverages such as:
  • Milkshakes
  • Smoothies
  • Nutrition or meal replacement drinks such as Boost, Ensure, Enu, and Orgain
• Maintain your muscle mass with physical activity such as:
  • Walking, jogging, playing tennis, or jumping rope
  • Strength training using weights, machines, or your own body weight
  • Yoga, Pilates, or barre
  • Housework and yard work

Tips for avoiding weight gain

Some people gain weight during cancer treatment. The weight gain can come from making unhealthful food choices or needing to take anticancer therapies that can stimulate appetite. Some tips to avoid excess weight gain include:

• Reducing your portion size
• Using a smaller plate
• Eating a larger proportion of plant-based foods
• Getting at least 30 minutes of physical activity each day

Dietary supplements

Multivitamin and mineral supplements can provide general health support for most people, at any age. Although no dietary supplement can prevent, treat, or cure cancer, people with cancer may benefit from certain vitamins and minerals.

Women of all ages need adequate amounts of calcium and vitamin D for bone health to prevent osteoporosis. Because certain cancer treatments can lead to bone loss, women undergoing cancer treatment may need more calcium and vitamin D in their diets.

To find out if you need more of these nutrients, your doctor will order a simple blood test. 

You can get healthy levels of calcium and vitamin D by:

• Consuming low-fat dairy products, fortified soymilk, eggs, and coldwater fish (a 3.5 oz can of salmon can contain 300 to 500 IU of vitamin D)
• Receiving 10 to 15 minutes of direct sunlight and taking 2 supplements (ideally with meals for increased absorption) each day:
  • Calcium supplement of 1,000 to 1,200 mg (taken in 2 doses)
  • Up to 2,000 IU total of vitamin D3

Published June 2019
Stanford Health Care © 2019