Nutrition Recommendations During and After Treatment

Approved by the Cancer.Net Editorial Board, 04/2016

People with cancer need to maintain a healthy body weight and eat nutritious foods. But the side effects of surgery, radiation therapy, and chemotherapy may cause a person to eat less and lose weight. Some treatments may cause weight gain for some patients.

Nutrition guidelines during cancer treatment

Here are some general nutrition recommendations for people receiving cancer treatment:

  • Maintain a healthy weight. For many people, this means avoiding weight loss by getting enough calories every day. For people who are obese, this may mean losing weight. Check with your doctor to find out if it is okay to try to lose weight during treatment. It may be better to wait until after treatment ends. If it is okay, weight loss should be moderate, meaning only about a pound a week.

  • Get essential nutrients. These include protein, carbohydrates, fats, and water.

  • Be as active as you can. For example, take a daily walk. If you sit or sleep too much, you may lose muscle mass and increase your body fat, even if you are not gaining weight.

Ways to get essential nutrients and manage a healthy weight

Nutrition counseling may help people with cancer get essential nutrients, such as protein, vitamins, and minerals. It can also help them maintain a healthy body weight.

For nutrition counseling, it’s important to visit a qualified professional. This means a registered dietitian (RD) or a registered dietitian nutritionist (RDN). Ask your health care team to help you find one of these professionals. You can also find a dietitian through the Academy of Nutrition and Dietetics.

Dietitians and other members of the health care team work with people to meet their nutritional needs. In addition to dietary counseling, they may recommend the following:

  • A multivitamin and/or specific vitamins or minerals that you aren’t receiving enough of

  • Liquid nutritional supplements and nutrient-dense beverages and snacks

  • Feeding tubes or nutrition support appropriate for your body

Side effects and nutrition

Cancer treatment often causes side effects, such as nausea, mouth sores, and taste changes that may make it difficult to eat or drink. Follow these tips to help get the nutrition you need:

  • If water tastes unpleasant to you, take in more liquid though other foods and drinks. For example: eat soup or watermelon, drink tea, milk, or milk substitutes. A sports drink is a great alternative. Consider flavoring your water by adding fresh cut fruit.

  • If food tastes bland, try seasoning it with flavorful spices. For example, try using garlic, cayenne, dill, and rosemary.

  • If your mouth is sore you may need to choose non-acidic and non-spicy foods until your mouth is healed.

  • Eat several small meals throughout the day instead of fewer large meals. Make sure you reach your calorie goal with these smaller meals.

  • If meat is no longer appealing, get protein from other foods. For example, try fish, eggs, cheese, beans, nuts, nut butters, tofu, or high-protein smoothies.

  • If you have a metallic taste in your mouth, suck on mints, chew gum, or try fresh citrus fruits. Use plastic utensils and cook in glassware. Also, try brushing your teeth before eating.

  • If you have mouth sores or a gum infection, use a blender to make the texture of vegetables and meats smooth. Try juicing or making smoothies because the extra moisture can help. For additional calories, add butter, mild sauces, gravy, or cream.

Some side effects are often treated with medication. If your side effects are affecting your hydration and nutrition, talk with your doctor or another member of your health care team.

The use of dietary supplements

Low-dose dietary supplements, such as multivitamins, may be helpful for people with cancer who are not able to get all of their nutrients through foods. Multivitamins are dietary supplements that contain most of the required daily vitamins, minerals, and trace elements. They may also contain some minerals such as calcium, magnesium, or iron. They are typically taken by mouth as a pill, capsule, tablet, liquid, or powder. High doses of specific nutrient supplements can be harmful. So talk with your doctor if you plan to take supplements.

Questions to ask your doctor before taking any dietary supplements include:

  • What are the benefits of taking this dietary supplement?

  • What are the possible side effects?

  • Are there risks to taking it?

  • Can taking dietary supplements interfere with my cancer treatment?

  • How much should I take and for how long?

  • Where can I learn more about dietary supplements?

Read more about dietary and herbal supplements.

Food safety

People in cancer treatment should be aware of food safety. Some treatments may weaken the immune system and could lead to an infection. A food-borne infection occurs when harmful bacteria, viruses, or fungi contaminate food and make you sick. Here are some basic food safety tips to reduce the risk of infection:

  • Wash your hands before and while you handle and prepare food.

  • Rinse vegetables and fruit thoroughly before eating them.

  • Handle and store food safely. For example:

    • Use separate cutting boards for meats and vegetables

    • Store meat and fish on the bottom shelf of the refrigerator

    • Do not thaw food on the counter or under warm running water

    • Refrigerate the foods after everyone has been served

  • Eat fully cooked foods. For example, do not eat eggs that are not cooked solid, and do not eat raw fish, oysters, or shellfish.

  • Do not eat or drink unpasteurized foods. This includes beverages such as unpasteurized cider, raw milk, and fruit juices, and foods such as cheeses made from unpasteurized milk.

  • Make sure the food you purchase is not past its sell by or expiration date and follow directions on proper storage.

Read more about food safety during and after cancer treatment.

Diet and nutrition after treatment

Most nutrition recommendations include eating fruits, vegetables, and whole grains. But the effect of specific dietary factors on cancer survival rates is not as well understood and is actively being studied. However, a healthy diet is important for cancer survivors because they may be at increased risk for other health conditions, such as heart disease, type 2 diabetes, and weakening of the bones.

To reduce the risk of other diseases, doctors generally recommend that cancer survivors follow common recommendations for good health. These include eating a nutrient-dense and plant-based diet, quitting smoking, maintaining a healthy weight, minimizing alcohol consumption, and staying physically active.

More Information

Spotlight On: Oncology Dietitians

Healthy Living After Cancer


Additional Resources

National Cancer Institute: Overview of Nutrition in Cancer Care and Eating Hints: Before, During, and After Treatment

Academy of Nutrition and Dietetics: Home Food Safety