Cancer and cancer treatment affect nutrition

When you’re healthy, eating enough food to get the nutrients and calories you need is not usually a problem. Most nutrition guidelines stress eating lots of vegetables, fruits, and whole-grain products; limiting the amount of red meat you eat, especially those that are processed or high in fat; cutting back on fat, sugar, alcohol, and salt; and staying at a healthy weight. But when you’re being treated for cancer, these things can be hard to do, especially if you have side effects or just don’t feel well.

During cancer treatment you might need to change your diet to help build up your strength and withstand the effects of the cancer and its treatment. This may mean eating things that aren’t normally recommended when you are in good health. For instance, you may need high-fat, high-calorie foods to keep up your weight, or thick, cool foods like ice cream or milk shakes because sores in your mouth and throat are making it hard to eat anything. The type of cancer, your treatment, and any side effects you have must be considered when trying to figure out the best ways to get the nutrition your body needs.

When your cancer was first diagnosed, your doctor talked with you about a treatment plan. This may have meant surgery, radiation therapy, chemotherapy, hormone therapy, biologic therapy ( immunotherapy), or some combination of treatments. All of these treatments kill cancer cells. But in the process, healthy cells are damaged, too. This damage is what causes cancer treatment side effects. Some of the more common side effects that can affect eating are:

You might – or might not – have any of these side effects. Many factors determine whether you’ll have side effects and how bad they’ll be. These factors include the type of cancer you have, the part of the body affected, the type and length of treatment, and the dose of treatment.

Many side effects can be controlled, and most go away over time after treatment ends. Talk with your cancer care team about your chances of having side effects and what can be done to help control them. After your treatment starts, tell your cancer care team about any side effects that aren’t controlled. Let them know if the medicines they’ve given you to help with side effects do not work, so that others can be used.

We have a lot more information on the different side effects of cancer treatment. Call us or visit our website for more details.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: July 15, 2015 Last Revised: July 15, 2015

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