Management

Loss of Appetite During Cancer Treatment

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Loss of appetite is a loss of the desire to eat. Not eating can lead to weight loss, which can cause weakness and severe tiredness (fatigue). This affects your ability to do daily activities. Good nutrition also helps your body heal and prevent and fight infection.


What causes loss of appetite?

Loss of appetite may be due to the cancer, or from the cancer treatment. You may have loss of appetite if you have any of these:

  • Tiredness
  • Pain
  • Taste changes, such as with sugar, salt, or meat
  • Side effects from medicines
  • Changes in your mood or feeling depressed
  • Nausea and vomiting
  • Constipation and diarrhea
  • Dehydration


Managing loss of appetite

You need to eat enough to maintain weight, do daily activities, recover from cancer treatment, and prevent illness.

To help you eat enough:

  • Eat small meals 5 to 6 times a day instead of 3 large meals.
  • Eat nutritious foods and drinks that are high in protein and calories. Try snacks such as hard-boiled eggs, peanut butter, or trail mix. Consider drinking a protein shake, milkshake, or smoothie when it is hard to eat.
  • Help family members plan meals you would like to eat.
  • Let others cook for you. Talk with them first about specific needs and requests.
  • Eat in pleasant surroundings with friends or family.
  • Eat your favorite foods any time of the day.
  • Try using plastic utensils and cook in a glass pot if foods have a metal taste.
  • If strong smells bother you, stay away from the area where food is being prepared. Eat cold foods instead of hot foods. Cold foods don't smell as much.
  • Do light exercise before meals.
  • Try new recipes.
  • Don't smoke. It can affect your sense of smell and change your sense of taste.
  • Take prescribed medicine 30 minutes before eating if you have nausea or pain.

To prevent feeling full too fast:

  • Don't eat high-fat foods.
  • Don't drink much at mealtime because you may feel full too quickly. Drink liquids at least 30 minutes before meals and throughout the day between meals so that you do not become dehydrated.
  • Chew food slowly.
  • Don't eat foods or have drinks that cause gas. These include cabbage or broccoli and fizzy drinks, such as beer or soda.


Food safety during cancer treatment

To prevent foodborne illness during cancer treatment:

  • Wash your hands well with soap and water before making or serving foods.
  • Clean all utensils and cooking or storage containers fully.
  • Thaw frozen foods in refrigerator or microwave, not at room temperature.
  • Cook all raw protein foods to safe temperatures. This includes eggs, meats, poultry, and fish.
  • Serve hot foods hot and cold foods cold. Don't let foods get to room temperature.
  • Refrigerate foods quickly.
  • Wash all fruits and vegetables before eating.
  • Use only pasteurized dairy products. Don't eat raw cheese or drink raw milk.
  • Don't use foods beyond expiration dates.


Working with your health care team

Tell your health care team if you have side effects from cancer treatment that affect your ability to eat. These can include dry mouth, mouth sores, nausea, vomiting, or constipation. Your doctor may change your medicine. Or they may prescribe medicine to help increase your appetite.

Your doctor may also ask you to:

  • Keep a daily food diary.
  • Weigh yourself regularly.
  • Write down changes in mood, appetite, and other feelings you have.

Call your doctor right away if you have any of the below:

  • Trouble drinking enough fluids
  • Trouble eating any food
  • Weight loss of 3 or more pounds in a week
  • Uncontrolled pain
  • Uncontrolled nausea and vomiting.
  • Dizzy feeling when you stand up
  • Any other problems or questions

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© 2026 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare provider's instructions.

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