Difficulty chewing occurs when pain in the mouth, stiffness or pain in the jaw muscles, or problems with the teeth make it difficult to eat certain foods, especially hard foods. It is important to work with your health care team to find ways to manage difficulty chewing because it may cause you to avoid certain foods (such as meats, fruits, or vegetables) or to eat smaller amounts of food, which can keep you from getting the calories and nutrients that your body needs.
Difficulty chewing often results from physical changes to the mouth, jaw, or tongue caused by cancer, especially oral and oropharyngeal cancers. It may also be a side effect of cancer treatment, such as chemotherapy, radiation therapy, or surgery. Side effects of cancer treatment that can cause chewing problems include:
- Mucositis  (soreness, pain, or inflammation in the mouth)
- Xerostomia  (dry mouth) from radiation therapy, chemotherapy, or some antidepressant and pain medications
- Gum disease, tooth decay, or tooth loss, which are possible long-term side effects of dry mouth, radiation therapy, or high-dose chemotherapy
- Infections of the mouth after radiation therapy or chemotherapy
- Pain and stiffness in the jaw muscles, either as a possible long-term side effect of radiation therapy to the head and neck or from jaw clenching or tooth grinding
- Mouth pain, which is caused by nerve damage from some types of chemotherapy
- Tissue and bone loss in the jaw, which is a possible long-term side effect of radiation therapy to the head and neck
- Physical changes to the mouth, jaw, or tongue as a result of surgery
- The inability to wear dentures because of pain or swelling in the mouth or gums
Relieving side effects—also called symptom management, palliative care , or supportive care—is an important part of cancer care and treatment. Talk with your health care team about any symptoms you experience, including any new symptoms or a change in symptoms, especially because chewing problems interfere with eating.
To learn how to chew more easily, especially if surgery has changed the structure of your mouth or tongue, you may see a speech therapist (a professional who specializes in helping people use the muscles in the mouth and throat). You may also want to visit a dentist, who will evaluate tooth or gum pain or denture problems that are causing difficulty chewing and provide treatment to help prevent future problems. You may receive a prescription for a special fluoride gel or mouth rinse to help prevent tooth decay or gum disease. Taking good care of your teeth and mouth with proper brushing and flossing will also help prevent dental problems.
In addition, your doctor or dentist may prescribe medications to reduce pain and inflammation. Some pain medications are mouth rinses used directly before eating. People with mouth infections, such as a fungal infection like thrush, may be given medication to treat the infection.
Chewing problems caused by jaw pain and stiffness are usually treated with muscle relaxants, physical therapy (such as massage, jaw exercises, or moist heat), or in some cases, surgery.
Diet and eating tips
Depending on the severity and cause of chewing problems, certain approaches may work better for some patients than for others. Try different types of foods with the goal of eating a nutritious diet that has enough calories, protein, and vitamins and minerals. Here are some more tips.
- Eat soft, smooth foods, such as yogurt, pudding, or ice cream.
- Mash or blend foods, or add blended vegetables or ground meats to casseroles or soups.
- Moisten dry foods with broth, sauce, butter, or milk.
- Take sips of water or other liquids while eating to keep the mouth and food moist.
- Try softer versions of your favorite fruits or vegetables, like applesauce or pureed carrots; switch to softer fruits and vegetables, such as bananas or peas; or consider eating baby food.
- Cut food into small bites, and chew slowly and thoroughly.
- If you are losing weight , eat smaller, more frequent meals that are high in protein and calories, such as eggs, milkshakes, casseroles, and nutritional shakes.
- Avoid dry, coarse, or hard foods and foods that need a lot of chewing.
Meet with a registered dietitian for additional help on eating a balanced diet.