June 14, 2021 | 8 minute read

Updated March 7th, 2022

The role of nutrition is to fuel, nourish and repair the body. Side effects from cancer and treatment can impact your diet and nutrition status and result in changes to your regular eating routine. Nutritional challenges such as loss of appetite, dry mouth, nausea or vomiting (to name a few) may arise before, during or after cancer treatment, but there are many ways to manage these side effects. It is important to note that each individual’s nutritional needs and eating habits will vary depending on the type of cancer, treatment and the individual themselves, but there are several tips that can help manage these common eating difficulties to minimize their severity and positively impact your overall wellbeing.

Fatigue

Fatigue is the one of the most common side effects of cancer treatment and can significantly affect your quality of life.

Here are some tips that can help:

• Keep healthy, easy to grab snacks readily available. Examples include trail mix, string cheese, whole grain crackers, almonds, bananas, hummus and veggie sticks.
• Add foods that are high in protein and calories to meals and snacks so when you are feeling up to eating you can make the most of it. Examples include avocado, nut butters, beans, granola, Greek yogurt and salmon.
• Prepare large quantities of food when you’re feeling best and freeze leftovers.
• Get help with meals and snacks from friends and family members.
• Get in activity and movement when possible. Research shows that regular activity can relieve fatigue and also enhance mood and appetite.

Loss of Appetite

Weight loss and undernutrition are common due to loss of appetite.

Try these tips to boost your nutrition:

• Eat several small meals (5-6 per day) instead of 3 large meals.
• Eat high-protein foods first in your meal while your appetite is strongest. Examples include beans, chicken, fish, meat, yogurt and eggs.
• Eat when you feel hungry.
• Add high calorie and protein foods to smoothies and milkshakes like avocados, whole-fat yogurts and oatmeal.

Nausea and Vomiting

Nausea is a common side effect of cancer treatment. It can sometimes be accompanied by vomiting.

Here are some tips to help with nausea:

• Instead of eating large meals, eat small amounts of food often and slowly
• Eat foods at room temperature or cooler. Hot food can often aggravate nausea due to strong odors.
• Eat sitting up.
• Drink beverages between meals instead of with a meal.
• Drink beverages cool or chilled and sip through a straw.
• Rinse out your mouth before and after eating.
• Suck on a hard candies or peppermint.

Foods to try:

• Toast and crackers, sherbet, popsicles, pretzels, canned fruits (peaches, pears, fruit cocktail) and broths

Foods to avoid:

• Foods that are fatty, greasy, fried, spicy, very sweet or that has a strong odor

Here are some tips to help with vomiting:

• Don’t eat or drink until your vomiting has subsided.
• Once vomiting is under control, try drinking small amounts of clear liquids.
• Try eating small amounts of soft foods when you are able to keep down clear liquids and gradually work your way back to your regular diet.

Food and Drinks to try:

• Soft foods such as cream of wheat, pudding, frozen yogurt and gelatin
• Cranberry juice, cool broth or flat soda

Foods to avoid:

• Spice, acidic and greasy foods

Diarrhea

Diarrhea or frequent, loose and watery bowl movement is another possible side effect.

Here are some tips to help with diarrhea:

• Drink plenty of liquids (aim for at least eight 8-ounce glasses each day). Healthy choices include water, diluted juice, broth and decaffeinated coffee or tea. Liquids at room temperature may be easier to tolerate.
• Eat small amounts of food throughout the day rather than large meals.

Foods to try:

• Rice, noodles, well cooked eggs, bananas, puréed vegetables, applesauce, white bread, skinned turkey or chicken, fish, mashed potatoes, yogurt, and kefir

Foods to avoid:

• Raw vegetables and fruits; high-fiber vegetables, like broccoli, corn, beans, cabbage, cauliflower and peas; onions and strong spices; greasy, fatty and fried foods; alcoholic beverages, caffeine-containing beverages

Constipation

Constipation can result from some cancer treatments and pain medications. Constipation can also happen if you are not eating enough fiber or drinking enough fluids.

Here are some tips to help with constipation:

• Drink more fluids, aiming for at least eight 8-ounce glasses a day. Liquids can help keep stools soft. Choices like water, prune juice, warm juices, decaffeinated teas and hot lemonade are great options to try.
• Eat more high fiber foods. Aim to eat at least 30g of dietary fiber per day.
• Increase your physical activity; aim for a walk every day.

Food and Drinks to try:

• High-fiber vegetables like broccoli, corn, beans, cabbage, cauliflower and peas; whole-grain breads
• Water, prune juice, warm juices, decaffeinated teas and hot lemonade. Aim for at least eight 8-ounce glasses a day.

Taste Changes

Changes in how foods taste can result from chemotherapy, radiation therapy and the cancer itself. Some experience bitter or metallic tastes. Each individual’s sense of taste can be affected differently.

Here are some tips to help with taste changes:

• Choose foods that appeal to you. Naturally sweet foods such as frozen melon, grapes or orange wedges may be particularly appealing, as may tart foods and beverages such as oranges, lemon yogurt or lemonade.
• If the taste of red meat is now less appealing, find healthy alternatives, such as chicken, turkey, fish, beans, nut butter, eggs or dairy products.
• Serve foods cold or at room temperature, which may improve how they taste.
• Brush your teeth and tongue and rinse your mouth regularly.
• Use plastic utensils instead of metal ones.
• Rinse your mouth several times a day with water; a baking soda mixture or alcohol-free mouthwash works the best.

Sore Mouth, Tongue or Throat

Soreness in the mouth or throat can result from cancer treatment or for other reasons. See your health practitioner to ensure that the soreness is not due to an infection.

Here are some tips to help with sore mouth:

• Prepare easy-to-swallow foods and include high-calorie and high-protein foods if you are having difficulty maintaining your weight.
• Cook foods until they are soft and tender and cut them into small pieces, or choose foods you can mash, blenderize or purée.
• Serve foods cool or at room temperature, which can be less irritating than foods that are either hot or cold. For some, cold foods such as sherbet or popsicles may soothe soreness.
• Drink through a straw.
• Avoid alcohol, which can irritate the cells lining your mouth.
• Rinse your mouth several times a day.

Foods to try:

• Bananas, applesauce, watermelon, canned fruits, peach, pear and apricot nectars, cottage cheese, yogurt, milkshakes, mashed potatoes, macaroni and cheese, custards, pudding, scrambled eggs, oatmeal

Foods to avoid:

• Hot and spicy foods, alcohol, hard to chew foods, citrus fruits and crunchy or rough foods

Dry Mouth

A dry mouth is most common after chemotherapy and radiation therapy to the head or neck area. A dry mouth due to a reduction in the flow of saliva can make it difficult to chew and swallow and may change the way food tastes.

Here are some tips to help with dry mouth:

• Stimulate saliva by sucking on lemon-flavored sugar-free candies, frozen grapes, sugarless popsicles, ice chips or cubes, and tart foods and beverages such as lemonade in small amounts.
• Opt for easy-to-swallow, moist foods such as those with broth, gravy, sauces and salad dressings.
• Avoid salty foods and alcohol.
• Keep water/fluids nearby. Avoid caffeine which can worsen dry mouth.
• Keep your lips moist by applying ointment or balm.

Good nutrition before, during and after cancer treatment can help you feel better—specifically help you keep your energy and strength, maintain your weight, lower risk of infection, recover faster and help you better tolerate treatment-related side effects. Unless otherwise advised, and if you can, all cancer survivors are advised to follow AICR’s Cancer Prevention Recommendations. Always, check with your health professional about what is right for you. Nutrition priorities may change during cancer treatment, recovery and survivorship and following AICR’s Recommendations may not always be the healthiest for an individual who has undergone cancer treatment. Working with a Registered Dietitian who specializes in Oncology can help you identify what your nutrition priorities are and how to achieve them. You can find a dietitian who specializes in oncology nutrition in your area here.

Take a look at AICR’s Healthy Recipes which have been specifically created to support cancer prevention and healthy survivorship. In the “survivor/during treatment” section, you will find a wide variety of recipes that can help combat treatment-related side effects. Another great resource is Cook for Your Life providing nutritionally sound recipes for those touched by cancer.

For more detailed information, visit AICR’s Treatment Tips page and download a free copy of AICR’s Cancer Resource: Living Well with Cancer and Beyond. Please note the information in this article is not meant to be a substitute for medical care.