Healthy Diet During Cancer Treatment

Cancer treatments can cause various side effects—including nausea and loss of appetite. But your loved one needs to eat well during treatment in order to fully recover from its effects.

All the methods of treating cancer—surgery, radiation therapy, chemotherapy, hormone therapy, and biological therapy (immunotherapy)—are very powerful. Although these treatments target the fast-growing cancer cells in your body, healthy cells can also be damaged. Healthy cells that normally grow and divide rapidly, such as those in the mouth, digestive tract, and hair, are often affected by cancer treatments. The damage to healthy cells is what produces the unpleasant side effects that cause eating problems.

Side effects of cancer treatment vary from patient to patient. The part of the body being treated, the type and length of treatment, and the dose of treatment determine whether side effects will occur.

The good news is that not everyone has side effects during treatment, and most side effects go away when treatment ends. Side effects can also be controlled with new drugs. Talk to your doctor about possible side effects from your treatment and what can be done about them.

Some eating problems are caused by the treatment itself. Other times, patients may have trouble eating because they are upset, worried, or afraid. Losing your appetite and nausea are two normal responses to feeling nervous or fearful. Once you get into your treatment period and have a better sense of what to expect and how you will react, these anxiety-related eating problems should get better.

While you are in the hospital or undergoing treatment, talk to your doctor, nurse, or a registered dietitian. They can answer your questions and give you suggestions for specific meals, snacks, and foods, and for dealing with any eating problems you may have. They can also help with dietary preferences that reflect various cultural and ethnic backgrounds. Feel free to talk to them if problems arise during your recovery as well. Ask them what has worked for other patients.

Remember, there aren’t any hard and fast nutrition rules during cancer treatment. Some patients may continue to enjoy eating and have a normal appetite throughout most of their cancer treatment. Others may have days when they don’t feel like eating at all; even the thought of food may make them feel sick. Here are some things to keep in mind:

  • When you can eat, try to eat meals and snacks with sufficient protein and calories; they will help you keep up your strength, prevent body tissues from breaking down, and rebuild tissues that cancer treatment may harm.
  • Many people find their appetite is better in the morning. Take advantage of this and eat more then. Consider having your main meal of the day early, and have liquid meal replacements later on if you don’t feel so interested in eating.
  • If you don’t feel well and can eat only one or two things, stick with them until you are able to eat other foods. Try a liquid meal replacement for extra calories and protein.
  • On those days when you can’t eat at all, don’t worry about it. Do what you can to make yourself feel better. Come back to eating as soon as you can, and let your doctor know if this problem doesn’t get better within a couple of days.
  • Try to drink plenty of fluids, especially on those days when you don’t feel like eating. Water is essential to your body’s proper functioning, so getting enough fluids will ensure that your body has the water it needs. For most adults, 6-8 cups of fluid a day are a good target. Try carrying a water bottle with you during the day. That may help you get into the habit of drinking plenty of fluids. 

Coping With Side Effects

This section offers practical hints for coping with treatment side effects that may affect your eating. These suggestions have helped other patients manage the same eating problems that you may have. Try all the ideas to find what works best for you. Share your needs and concerns with your family and friends, particularly those who prepare meals for you.

Loss Of Appetite

Loss of appetite or poor appetite is one of the most common problems that occurs with cancer and its treatment. No one knows exactly what causes loss of appetite. It may be caused by the treatments or by the cancer itself. Emotions such as fear or depression can also take away a person’s appetite. Ask a nurse or social worker about ways to lessen these emotional difficulties. Sometimes it is the side effects of treatment such as nausea, vomiting, or changes in food’s taste or smell that make a person feel like not eating. If this is the cause, work with your doctor or nurse to get the side effects under better control.

For some people, loss of appetite happens for just a day or two; for others, it’s an ongoing concern. Whatever the reason, here are some suggestions that might help:

  • Try liquid or powdered meal replacements, such as “instant breakfast,” during times when it is hard for you to eat food.
  • Try frequent small meals throughout the day, rather than fewer big ones. It may be easier to eat more that way, and you won’t get so full.
  • Keep snacks within easy reach so you can have something whenever you feel like it. Cheese and crackers, muffins, ice cream, peanut butter, fruit, and pudding are good possibilities. Take a portable snack with you when you go out, such as peanut butter crackers or small boxes of raisins.
  • Even if you don’t feel like eating solid foods, try to drink beverages during the day. Juice, soup, and other fluids like them can give you important calories and nutrients. Milk-based drinks also provide protein.
  • If possible, try having something at bedtime. It won’t affect your appetite for the next meal.
  • Sometimes, changing the form of a food will make it more appetizing and help you eat better. For example, if eating whole, fresh fruit is a problem, try mixing fruit into a milkshake.
  • Try softer, cool, or frozen foods, such as yogurt, milkshakes, or popsicles.
  • Take advantage of times when you do feel well, and have a larger meal then. Many people have a better appetite first thing in the morning, when they are well rested.
  • During meals, sip only small amounts because drinking may make you feel full. If you want to have more than just a small amount to drink, have it 30-60 minutes before or after a meal.
  • Make mealtimes as relaxed and pleasant as possible. Presenting food or meals in an attractive way may also help.
  • If your doctor allows, have a small glass of wine or beer during a meal. It may help to stimulate your appetite.
  • Regular exercise may help your appetite. Check with your doctor to see what options are open to you.

Commercial Products:

If you cannot get enough calories and protein from your diet, commercial meal replacements such as drinks, “shakes,” and “instant breakfast” powders may help. Other products also can be added to any food or beverage. These supplements are high in protein and calories and have extra vitamins and minerals. They come in liquid, pudding, and powder forms. Most commercial meal replacements contain little or no lactose. However, it is important to check the label if you are sensitive to lactose. Your nurse or a registered dietitian can tell you which products are best for you and which ones are available in your area.

Most of these products need no refrigeration until you open them. That means you can carry them with you and have them whenever you feel hungry or thirsty. They are also good chilled as between-meal or bedtime snacks. You may want to take a can with you when you go for treatments or other times when you may have a long wait.

Many supermarkets and drugstores carry a variety of commercial liquid meal replacements. If you don’t see these products on the shelf, ask the store manager if they can be ordered.

Weight Loss

Many cancer patients lose weight during their cancer treatment. This is partly due to the effects of the cancer itself on the body. Also, if you’ve lost your appetite and are eating less than usual because of your treatment or emotional worries, you may lose weight.

Weight Gain

Some patients find their weight does not change during treatment. They may even gain weight. This is particularly true for breast, prostate, and ovarian cancer patients taking certain medications or who are on hormone therapy or chemotherapy.

It is important not to go on a diet right away if you notice weight gain. Instead, tell your doctor so you can find out what may be causing this change. Sometimes, weight gain happens because certain anticancer drugs can cause your body to hold on to excess fluid. This condition is called edema. The weight comes from the extra water. If this is the case, your doctor may ask you to talk with a registered dietitian for guidelines on limiting the amount of salt you eat. This is important because salt causes your body to hold extra water. Your doctor may also want to prescribe a diuretic. This is a medication that causes your body to get rid of excess fluid.

Breast cancer patients with a primary diagnosis of cancer may be different. Over half of them may actually gain weight rather than lose during treatment. Because of this, many of the recommendations for breast cancer patients do emphasize a lower fat, reduced calorie diet similar to those provided to patients after cancer treatment has been completed.

Weight gain may also be the result of increased appetite and eating extra food and calories. If this is the case and you want to stop gaining weight, here are some tips that can help. Talk to a registered dietitian for more guidance:

  • Emphasize fruits, vegetables, and breads and cereals.
  • Choose lean meats (lean beef or pork trimmed of fat, chicken without skin) and low-fat dairy products (skim or 1% milk, light yogurt).
  • Cut back on added butter, mayonnaise, sweets, and other extras.
  • Choose low-fat and low-calorie cooking methods (broiling, steaming).
  • Avoid eating high-calorie snacks between meals.
  • If you feel up to it, increase the amount of exercise you get.

© Copyright FamilyCare America, Inc. All Rights Reserved.

Reprinted from Eating Hints For Cancer Patients Before, During, and After Treatment, NIH Publication #98-2079, developedby the United States National Institutes of Health National Cancer Institute.

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