Non-Irritating Foods to Eat When You Have Mouth Sores

What You Can Do About Oral Mucositis

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The loss of appetite is common when undergoing cancer treatment, particularly if you get a common side effect called oral mucositis that causes mouth sores. To ensure proper nutrition to help you heal, you need to find non-irritating foods that you can eat even if you have mouth sores.

This article explains why mouth sores occur in people undergoing cancer treatment. It also lists the types of food you can and cannot eat—as well as the way to eat—to better cope with treatment-induced oral mucositis.

Person tossing blueberries into blender to make a smoothie

Oscar Wong / Getty Images

How Cancer Treatment Causes Mouth Sores

Over 40% of people undergoing certain cancer treatments will develop oral mucositis. It is most commonly associated with chemotherapy but can also occur with radiation therapy to the head or neck.

Oral mucositis is an especially common occurrence when exposed to the chemotherapy drugs 5-fluorouracil (5-FU) or Evomela (melphalan). Other chemotherapy drugs can do the same.

Treatment-induced oral mucositis is the result of the following processes:

  1. Whenever cells are damaged by chemotherapy or radiation, they release unstable atoms called free radicals.
  2. This, in turn, triggers the release of inflammatory chemicals called cytokines and metalloproteinase that break down a structural protein called collagen, causing tissues to thin and form ulcers.
  3. When this occurs in the mouth, natural bacteria quickly move into the sores, causing infection, inflammation, and pain.

The sores can often be extremely painful, making it difficult to eat, talk, and swallow. The sores may even extend into the esophagus that carries food from the mouth to the stomach.

Foods to Eat If You Have Mucositis

Generally speaking, you will want to eat foods that are soft, non-acidic, non-spicy, and not overly hot if you have oral mucositis. The less you have to chew, the better.

Among the foods recommended for people struggling with oral mucositis are:

  • Scrambled, poached, or boiled eggs
  • Canned tuna fish
  • Stewed meats
  • Soft noodles and pasta
  • Well-cooked white rice
  • Mashed vegetables, including potatoes sweet potatoes, peas, carrots, etc.
  • Creamed spinach or corn
  • Creamed or pureed soups
  • Baked beans
  • Tofu
  • Dairy products like milk, yogurt, and cottage cheese
  • Soft white bread
  • Cooked cereals, such as cream of wheat or thinned oatmeal
  • Pancakes
  • Applesauce
  • Bananas
  • Watermelon, cantaloupe, papaya, and honeydew melon
  • Soft stone fruits with thin skins, like peaches and nectarines
  • Stewed or baked fruits
  • Smooth peanut butter
  • Custards and puddings
  • Gelatin desserts
  • Popsicles, ice cream, and frozen yogurt
  • Protein shakes, smoothies, and liquid nutritional supplements
  • Caffeine-free tea
  • Non-acidic juices, like apple juice or fruit nectars

Food to Avoid

There are certain foods that can aggravate mouth sores and make the pain worse. Even before starting cancer treatment, take heed of the types of food you should avoid, including:

  • Tough cuts of meat
  • Raw or undercooked vegetables
  • Tough or chewy bread, like bagels
  • Crunchy foods, such as pretzels, crackers, chips, or dry cereal
  • Tart or acidic foods, including tomatoes and citrus fruits
  • Salty or spicy foods
  • Nuts or seeds
  • Hard or stringy fruits, like raw apples or mangos
  • Fruits with skins, like plums
  • Fruits with little seeds, like strawberries, that can get stuck in sores
  • Hot foods, including soup and piping-hot beverages
  • Caffeinated beverages, including coffee, black tea, and colas
  • Alcohol, including beer, wine, and liquor

How to Eat if You Have Oral Mucositis

Oral mucositis can be difficult to avoid when undergoing cancer treatment. Still, there are things you can do to get the nutrition you need without worsening the pain. This not only involves the types of food you eat but also the way that you eat.

Among some of the more helpful tips:

  • Eat smaller, more frequent meals: Instead of three large meals a day, try five to six snack-sized meals that place less stress on the mouth.
  • Take smaller bites: It often helps to cut your food into small pieces before starting to eat.
  • Puree your food: If your mouth is too sore to chew, get a blender and puree it.
  • Moisten your food: Gravy and broth are not only ideal for softening food but also provide added nutrition. You can also make food more slippery with a splash of olive oil or canola oil.
  • Use a straw: Sucking drinks through a straw can help you bypass mouth sores.

Nutritional Goals

It is important to maintain balanced nutrition each day. To do so, you need to eat:

  • Two servings of protein
  • Two servings of dairy
  • Five servings of fruits and vegetables
  • Eight to 10 glasses of water or liquids

Coping with Oral Mucositis

In addition to being mindful of what and how you eat, the following can also help you manage mouth sore pain if you have oral mucositis:

  • Drink ice water or suck on ice chips to cool the mouth and bring down inflammation.
  • Take care of your teeth and gums by gently brushing and flossing.
  • Gargle with Magic Mouthwash, which is specifically formulated for oral mucositis.
  • Use an over-the-counter oral numbing spray like Chloraseptic.
  • Quit smoking, which not only increases the risk of oral mucositis but makes it worse.

How to Deal With Dry Mouth

In addition to mouth sores, radiation treatment can cause dry mouth (xerostomia). If you are experiencing dry mouth in addition to mouth sores, try the following to help keep the moisture levels up:

  • Chew sugarless gum to promote saliva production.
  • Use a saliva substitute like OraCoat or Biotene.
  • Stay well hydrated.
  • Snack on water-filled fruits like grapes and watermelon,
  • Avoid caffeine and alcohol, both of which can dry the mouth.
  • Quit cigarettes.

Summary

Mouth sores are a side effect of chemotherapy and radiation. They can make it difficult to eat, drink, and swallow. You can relieve the pain with things like ice chips, Magic Mouthwash, numbing sprays, and eating smaller, more frequent meals.

The foods you eat can also make a big difference. Choose foods that are soft, well-cooked, cold, or pureed. Avoid spicy, hot, salty, acidic, or crunchy foods, as well as caffeine and alcohol.

A Word From Verywell

Preparation almost always makes cancer treatment easier. Before you even start chemotherapy or radiation, ask your cancer specialist or care team about their recommendations for managing mouth sores.

If mouth sores are undermining your nutrition or quality of life, let your doctor know. In severe cases, a medication called Kepivance (palifermin) can be prescribed. Delivered intravenously (into a vein), Kepivance stimulates the growth of mucosal tissues and helps reduce the size and pain of mouth sores.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Barbosa SCM, Pereira VBM, Wong DVT, et al. Amifostine reduces inflammation and protects against 5-fluorouracil-induced oral mucositis and hyposalivation. Braz J Med Biol Res. 2019;52(3):e8251. doi:10.1590/1414-431X20188251

  2. Chaveli-Lopez B, Bagan-Sebastian JV. Treatment of oral mucositis due to chemotherapy. J Clin Exp Dent. 2016 Apr;8(2):e201–9. doi:10.4317/jced.52917

  3. American Cancer Society. American Cancer Society guideline for diet and physical activity.

  4. Georgiou M, Patapatiou G, Domoxoudis S, Pistevou-Gompaki K, Pananikolaou. Oral mucositis: understanding the pathology and management. Hippokratia. 2012 Jul-Sep;16(3):215–6.

  5. Villa A, Connell CL, Abati S. Diagnosis and management of xerostomia and hyposalivationTher Clin Risk Manag. 2015;11:45-51. doi.org/10.2147/TCRM.S76282

  6. Lauritano D, Petruzzi M, Di Stasio D, Lucchese A. Clinical effectiveness of palifermin in prevention and treatment of oral mucositis in children with acute lymphoblastic leukaemia: a case-control study. Int J Oral Sci. 2014 Mar;6(1):27-30, doi:10.1038/ijos.2013.93

By Suzanne Dixon, MPH, RD
Suzanne Dixon, MPH, MS, RDN, is an award-winning registered dietitian and epidemiologist, as well as an expert in cancer prevention and management.