Side Effect: Altered Taste

A change in taste, also called dysgeusia, is when your sense of taste is impaired, abnormal, or is unpleasant. This can be a common side effect of chemotherapy, radiation, vitamin deficiencies, infection or other conditions.

You may notice that foods and beverages that you used to eat and drink now taste foul, bland, salty, rancid, or even metallic. Certain foods with strong flavors (bitterness, sweetness, and salty foods) are more likely to taste different. Sometimes, different foods can all taste the same or high-protein foods likes meat can leave a metallic or chemical aftertaste. It is important to recognize changes in taste because it can lead to malnutrition, loss of appetite and weight loss.

Dysgeusia is a common side effect and can develop within days to weeks of starting cancer treatment. There are many reasons that someone may have dysgeusia. Some of the most common causes include:

• Low levels of zinc (zinc deficiency)
• Radiation or surgery around the head and neck
• Dry mouth
• Changes in oral cavity flora
• Infection (example: COVID-19)
• Mucositis
• Platinum chemotherapy (cisplatin (Platinol®), carboplatin (Paraplatin®))
• Anthracycline chemotherapy (example: doxorubicin (Adriamycin®)
• Other chemotherapy agents (examples: cyclophosphamide (Cytoxan®), 5-fluorouracil (5-FU))
• Oral chemotherapy (example: sunitinib (Sutent®), vismodegib (Erivedge®))
• Antihistamines

Preventing dysgeusia in patients with cancer can be challenging since it is a side effect of cancer treatment. However, there are some interventions that can help reduce the severity of altered taste:

• Maintain good oral hygiene.
• Stop smoking and chewing tobacco if using these products prior to starting treatment.
• Zinc supplementation
• Taking selenium or amifostine during radiation treatment (talk to your doctor to see if this is right for you)
• Eat cold or lukewarm foods and frozen fruits.
• Add seasoning and/or sugar to foods.
• Eat protein products with a mild flavor.
• Eat less foods that have a bitter or metallic taste
• Drink plenty of fluids
• Treat underlying dry mouth
• Eat smaller meals throughout the day instead of three large meals for breakfast, lunch, and dinner.
• Avoid foods with strong smells.

Treating dysgeusia can be challenging because taste alterations vary in severity and is specific to the person. There is limited evidence regarding the benefit of specific treatments for dysgeusia. Some studies suggest that oral rinses or flavor enhancers such as monosodium glutamate (MSG) or citric acid may improve taste perception and increase food intake. Additionally, zinc supplementation, and taking dietary supplements with glutamine, lactoferrin and fish oil may be helpful (talk to your doctor before starting these supplements).

New foods may need to be incorporated into the diet as previously enjoyed foods may not taste the same. Plain drinking water can often bring out a metallic taste. If so, incorporating low-sugar flavored beverages can help with the flavor. Eating healthy foods and drinking plenty of fluids are important, especially while undergoing chemotherapy. Talking to a registered dietician can help create specific meal plans for patients with taste disturbances.