Tips for Eating During Immunotherapy Treatment

Your diet during cancer treatment should provide energy, nourishment, and hydration for a physically and emotionally challenging time. But the side effects from cancer treatment, including immunotherapy treatment, can make it hard to eat the way your body needs. And when it comes to immunotherapy, a healthy diet can even help you have a better response to treatment. 

Read on to learn more about how your diet can support you during this time, and what you can do in your diet to help manage treatment side effects.

What is immunotherapy?

Immunotherapy is a growing type of cancer treatment that uses your body’s own immune system to treat the cancer. There are different types of immunotherapy, such as the use of targeted antibodies, vaccines, or viruses. These are often used with surgery, chemotherapy, or radiation. 

Why is your diet important during immunotherapy treatment?

Your nutrition and diet are very important during cancer treatment. Your food provides protein, vitamins, minerals, fats, sugars, and hydration — giving you the strength and stamina you need throughout the treatment process. 

Science is beginning to show that a healthy diet — including a high-fiber diet — may even help improve your response to immunotherapy.

In addition to helping with improving response to treatment, good nutrition during cancer treatment can help you:

• Keep a healthy body weight

• Recover more quickly from surgery

• Grow new healthy cells and tissues

• Maintain muscle mass

• Manage side effects from treatment

Talk with your healthcare provider about specific dietary recommendations for you. It may be helpful to see a nutritionist as there may be dietary factors that can improve your immune functioning during immunotherapy, such as by following a Mediterranean or ketogenic diet. 

What are the side effects of immunotherapy?

Side effects of immunotherapy may be different from conventional cancer treatments and can depend on the type of immunotherapy used. Side effects are often due to overstimulation of the immune system or the immune system attacking healthy tissues. Side effects of immunotherapy may include:

• Flu-like symptoms

• Nausea and diarrhea

• Body aches or arthritis

• Skin rash or mouth sores

• Severe infections or autoimmune disorders

When going through immunotherapy treatment, it’s important to talk with your healthcare team about any side effects you experience.

How can my diet help me manage the side effects of immunotherapy?

Immunotherapy can impact the immune system and even attack healthy cells. This can lead to side effects such as appetite changes, nausea, and vomiting, or weight loss. There may be some dietary changes that could help manage these, for example:

• For decreased appetite: Try eating small regular snacks or meals throughout the day instead of three large meals. Try to set reminders to eat and drink and keep snacks and water near you.

• For nausea and vomiting: Since having an empty stomach can worsen nausea, try eating regular small snacks every couple of hours. Try eating plain food like rice, pasta, breads, and crackers. You can try ginger tea or candies to help with nausea. It’s important to hydrate regularly, and if water is hard to drink you can try tea, juice, coconut water, or mineral water. Consider talking with your healthcare provider about medication options that can help.

• For constipation: Try to stay hydrated and increase fiber in your diet. You can also try snacking on prunes and dried fruits. Talk with your healthcare provider about other treatment options, such as stool softeners.

• For diarrhea: Avoid foods that may make diarrhea worse such as alcohol, caffeine, greasy foods, and dairy. When you have diarrhea, try to have foods like apples, bananas, oatmeal, breads, white rice, and a lot of fluid with electrolytes (such as coconut water or soup broth).

• For dry mouth: You can increase your saliva by sucking on sour candies or chewing gum. You may want to avoid dry or hard-to-swallow foods like breads, peanut butter, or baked potatoes. Adding lemon or other citrus to your water may also help. 

• For mouth pain or sores: Try eating cooked stews that are easy to chew, or soft foods like smoothies and yogurt. Try avoiding foods that could cause more pain like acidic foods (citrus, tomatoes, vinegar), or alcoholic or carbonated drinks. Cold or frozen foods like popsicles can be soothing, and it may help to use a straw or suck on ice. 

• For weight loss: Maintaining weight is important during cancer treatment. Try adding healthy foods that are high in calories such as oils and butters, nuts and nut butters, and cheeses. Try eating more regular small meals throughout the day. Look for high-protein foods like beans, meats, fish, poultry, and eggs. You may also talk with your healthcare provider about if adding a liquid nutritional supplement to supplement your diet would be right for you. 

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Written by:

Christina Palmer, MD

Christina Palmer, MD, is a board-certified family physician with a special interest in chronic care management, women’s health, mental health, and preventive care. She has over 10 years of experience in primary care research, innovation, and practice.

Edited by:

Kelsey Abkin

Kelsey Abkin has been working as a journalist since 2016. She has held many titles throughout her career, including editor, content strategist, digital strategist, and writer.

Reviewed by:

Sophie Vergnaud, MD

Sophie Vergnaud, MD, is the Senior Medical Director for GoodRx Health. An experienced and dedicated pulmonologist and hospitalist, she spent a decade practicing and teaching clinical medicine at academic hospitals throughout London before transitioning to a career in health education and health technology.

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