Cancer treatment often affects a person's eating habits and nutritional needs. While it is important for people with cancer to maintain a healthy body weight and eat a nutritious diet, it may be difficult to eat the same foods as before treatment, depending on the type of treatment a person is receiving. The side effects of surgery, radiation therapy, and chemotherapy may cause a person to eat less and lose weight.

Nutrition recommendations during cancer treatment

Here are some general nutrition recommendations for people undergoing cancer treatment.

• Maintain a healthy weight. For many people, this means avoiding weight loss by getting enough calories on a daily basis. In people who are overweight, this may mean losing some weight (moderately, about one to two pounds a week).
  
  
• Get essential nutrients the body needs, such as protein, carbohydrate, vitamins, minerals, and water.

Ways to get essential nutrients and manage a healthy weight

Dietary counseling may help people with cancer maintain a healthy body weight and get the appropriate nutrients into their diet. Ask your health care team for a referral to a registered dietitian (RD). You can also find a dietitian through the American Dietetic Association.

Dietitians and other members of the health care team can work with people to meet their nutritional needs, which, in addition to dietary counseling, may include:

• Dietary supplements, such as multivitamins and calcium
  
  
• Liquid meal replacements and nutrient-dense beverages and snacks
  
  
• Feeding tubes
  
  
• Parenteral nutrition (getting nutrients into the body in a manner other than through the digestive tract; for example, intravenous [IV] injection). This strategy is for those who are exceptionally underweight and not getting enough nutrition before cancer surgery, or those whose digestive tracts are not functioning (as in people who have had parts of the stomach, pancreas, or colon removed by surgery).

The use of dietary supplements

Low-dose dietary supplements (such as multivitamins) may be appropriate for people with cancer who are not able to get all of their nutrients through foods. Dietary supplements are products that have one or more dietary ingredients, including vitamins and minerals. They are typically taken orally (by mouth) as a pill, capsule, tablet, liquid, or powder. Because high doses of specific supplements can be harmful, it is important to talk with your doctor about individual supplements.

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

• What are the benefits of taking this dietary supplement?
  
  
• What are the possible side effects of taking this dietary supplement?
  
  
• Are there risks to taking this dietary supplement?
  
  
• Can taking dietary supplements interfere with my cancer treatment (surgery, chemotherapy, radiation therapy)?
  
  
• 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 undergoing cancer treatment need to be aware of food safety, since cancer treatment may weaken the immune system and lead to an infection. An infection occurs when harmful bacteria, viruses, or fungi (such as yeast) invade the body, and the immune system is not able to destroy them quickly enough. Here are some basic food safety tips to reduce the risk of infection.

• Wash hands before and during the handling and preparing of food.
  
  
• Handle and store food appropriately.
  
  
• Eat thoroughly cooked foods.
  
  
• Avoid drinking unpasteurized beverages (for example, unpasteurized cider, raw milk, and fruit juices). Be sure to read labels, as unpasteurized products can be found at some stores, local orchards, roadside stands, or farmers' markets.

Read more about food safety during and after cancer treatment.

Diet and nutrition after treatment

After treatment ends, a person's follow-up care should include monitoring for a risk of recurrence (return of the cancer) or the development of a second cancer. In addition, cancer survivors may be at increased risk for other health conditions, such as heart disease, type 2 diabetes, and osteoporosis (weakening of the bones). To reduce the risk of other diseases, doctors generally recommend that survivors follow common recommendations for good health, such as quitting smoking, maintaining a healthy weight, and staying physically active. Although most nutrition recommendations include eating fruits, vegetables, and whole grains, the effect of specific dietary factors on cancer survival rates is not as well understood and is actively being studied.

More Information

General Nutrition Guidelines

Diet and Nutrition Resources

Nutrition and Cooking Resources for People Living With Cancer

Additional Resources

National Cancer Institute: Eating Hints for Patients Before, During, and After Treatment

Foodsafety.gov

American Dietetic Association: Home Food Safety

Last Updated: November 25, 2009