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Good nutrition during cancer treatment is important to help your body stay strong, keep your immune system working as well as possible and may help you tolerate treatment.

Recommendations on diet and nutrition for cancer patients is not a one-size-fits-all diet. Treatment and its side effects may change the way your body processes food. You may need more of a certain kind of food than you did before. For example, people being treated for cancer sometimes need more protein and calories to help improve energy, heal body tissue and fight off infection. You may be told to avoid other foods because they are more likely to cause infection.

However, healthy eating can help your body feel, look and work better. Good nutrition is especially important when your body is fighting disease. The first step to eating healthier is to talk with your health care team. They understand your health needs and can let you know of any foods to eat more of or avoid based on your diagnosis and treatment plan.

Healthy eating may help you:

  • Get the nutrition you need
  • Tolerate the side effects of treatment
  • Lower your risk of infection
  • Prevent and manage other health problems, such as diabetes, high blood pressure and osteoporosis
  • Maintain a healthy weight
  • Feel your best

Cancer and cancer treatment can change your body’s nutritional needs. Even if you ate well before, it is a good idea to ask your team about healthy eating during treatment to ensure that you are getting the nutrients you need to help your body handle the rigors of treatment and heal faster.

Ask your health care team for eating advice specific to your situation. Always listen to your team first but these general guidelines may be useful.

Most Cancer Guidelines Stress:

  • Eating vegetables and fruits, if possible at least five servings/day
  • Eating dark green leafy and cruciferous vegetables such broccoli, spinach and kale daily
  • Limiting your intake of red meat, sugar and high-fat foods
  • Eating whole grains and legumes such as whole wheat bread, brown rice and beans
  • Avoiding alcohol
  • Limiting the amount of salt-cured, smoked and pickled foods 
  • Drinking fluids to stay hydrated

Tips to Increase Protein and Calorie Intake:

  • Try to eat small snacks throughout the day.
  • Plan to eat your biggest meal when you are likely to be hungriest.
  • Drink fluids between meals instead of during meals to avoid feeling full faster.
  • Drink high-calorie beverages such as protein shakes or milkshakes.
  • Include whole milk or yogurt and other high-calorie foods such as eggs, gravies, nuts and lean meat and poultry in your diet.

Foods to Avoid:

  • Raw meat, poultry, fish, eggs or shellfish, including smoked fish and sushi
  • Unpasteurized dairy products including soft cheeses made from unpasteurized milk
  • Unwashed produce and fruits

Cancer treatment can change the way the body uses food, cause stomach distress and affect your appetite and comfort eating. Side effects vary from person to person, and can be relatively mild or more serious. Always tell a member of your health care team about the side effects you are experiencing. They may be able to recommend medications to prevent or treat some eating-related side effects. Some side effects can become serious if untreated so it is important to report side effects as soon as you notice them. Consider asking to speak with a dietician or other professional who can advise you on healthy eating if you are concerned about nutrition or weight gain or loss, or having trouble finding foods you can eat comfortably. Tips to Help Prevent and Manage Eating Problems:

Loss of Appetite or Weight Loss

  • Eat more small meals instead of three big meals/day.
  • Keep high calorie foods and drinks nearby for times when you are hungry or have an appetite.
  • Plan your largest meal for a time when you are likely to be hungriest.
  • Snack regularly even when you are not hungry.
  • Exercise lightly to increase your appetite.
  • Drink beverages between meals rather than with the meals. 

Weight Gain

  • Eat foods such as vegetables, fruits, whole grains and beans that are low in calories and high in fiber to help you feel full.
  • Eat smaller portions of food.
  • Eat only when you are hungry.
  • Exercise regularly.


  • Avoid foods that are spicy, fatty, overly sweet or have a strong smell.
  • Keep track of the foods, smells or events that trigger your nausea and try to avoid them.
  • Keep crackers and ginger tea on hand. 
  • Ask your health care team about medications to prevent or manage nausea.


  • Drink plenty of liquids to prevent dehydration.
  • Eat small amounts of food throughout the day rather than three large meals.
  • Tell your health care team if the diarrhea lasts for more than 24 hours or if you are having large amounts of diarrhea; this may be a sign of infection


  • Drink more liquids, including water, prune juice or warm drinks
  • Limit foods that cause gas such as carbonated beverages, beans, onions, cauliflower, broccoli and cucumbers.
  • If recommended by your health care team, increase your fiber intake by eating bran, fresh fruit, prunes or other foods high in fiber.
  • Ask your health care team about laxatives, fiber supplements or other medications to prevent or treat constipation.
  • Tell your health care team if you do not have a bowel movement in 72 hours or experience abdominal pains or cramping. These may be signs of a bowel obstruction.

Taste Changes

  • Keep favorite foods or foods that sound most appealing nearby. Try moist foods, beverages or foods that are naturally sweet or tart.
  • Brush your teeth and tongue, and rinse your mouth, regularly to clean your taste buds.
  • Eat foods at cold or room temperatures to reduce their taste and smell.
  • Add sugar to foods to enhance the taste.
  • Suck on lemon drops or mint candies. 

Dry Mouth

  • Avoid salty foods and alcohol, including mouth rinses that contain alcohol.
  • Don’t smoke and avoid secondhand smoke whenever possible. Talk to your health care team about ways to stop smoking.
  • Stimulate saliva by eating and drinking tart foods or sucking on lemon-flavored candies.
  • Moisten foods with sauces and gravies.
  • Tell your health care team about any small, white patches in your mouth as they may be a sign of infection.

Sore Mouth

  • Eat soft and easy to chew foods such as yogurt, pudding and applesauce.
  • Add gravy or sauce to your food to help you swallow.
  • Avoid carbonated beverages, alcohol and acidic, course, spicy or salty foods.
  • Blend foods to make them easier to eat.

Dietary supplements promise a fast and easy way to add nutrition to your diet. This can be tempting to people being treated for cancer who may be losing weight or nutrients due to nausea, loss of appetite or diarrhea.

It is very important that you use caution and speak with your health care team before taking any dietary supplements, including over-the-counter vitamins, minerals, herbs, amino acids, enzymes and other products sold as nutritional supplements.

There is still a lot to be learned about dietary supplements and cancer treatment. Doctors know that supplements can act as medicines, and may interfere with chemotherapy or other medications used to treat cancer. Certain dietary supplements can cause skin sensitivities that may be harmful to people receiving radiation treatment. Talk with your health care team about the potential benefits, risks and side effects associated with any supplements you are considering.

If you are concerned that you are not getting the nutrition you need, ask to talk to a dietitian or health care professional who can offer advice on healthy eating. The nutrients you need probably can be found in foods, and foods are often better sources of nutrients than supplements. Use this list of nutrition-rich foods to get started.