Chemotherapy frequently causes a change in the sense of taste (dysgeusia), or sometimes a complete loss of taste (ageusia). This common side effect affects an estimated 50% to 75% of individuals undergoing treatment. Managing these taste alterations is important for maintaining adequate nutrition and well-being during cancer therapy.
The Direct Link: Why Taste Changes Occur
The mechanism behind chemotherapy-induced taste change stems from the way these drugs work throughout the body. Chemotherapy agents are designed to target and destroy cells that divide rapidly, a characteristic of cancer cells. Unfortunately, several healthy cells also divide quickly, including the specialized cells found in the taste buds on the tongue.
These taste receptor cells are constantly being renewed, making them highly vulnerable to damage from chemotherapy drugs. When damaged, the signaling pathways communicating taste information to the brain are disrupted, leading to altered taste perception. Reduced saliva production, known as dry mouth or xerostomia, is another contributing factor. Saliva is necessary to dissolve food compounds and bring them into contact with the taste buds.
Specific Ways Taste Is Altered
Patients report a variety of sensory experiences, most commonly a persistent metallic or chemical taste. This abnormal sensation, often described as “metal-mouth,” can be pronounced after consuming red meat or using metal utensils. Certain chemotherapy drugs, especially those containing platinum, are thought to contribute to this metallic taste.
Beyond the metallic sensation, there can be a heightened perception of bitterness, making certain foods, like coffee or chocolate, unpalatable. Conversely, the ability to detect other tastes may be diminished; many people find that foods taste bland, flat, or lose all flavor intensity. The perception of salty flavors appears to be one of the most compromised taste qualities during treatment.
Managing Taste Changes During Treatment
Several dietary and behavioral adjustments can help mitigate the effects of taste changes and make eating more tolerable. If experiencing a metallic taste, switching from metal cutlery to plastic utensils can help. It is also helpful to avoid canned foods, choosing items packaged in glass or plastic instead, as the packaging may worsen the metallic sensation.
To counteract a lack of flavor or blandness, incorporating strong, natural flavors into meals is often effective. Marinating meats in sweet-and-sour sauces, fruit juices, or salad dressings can mask undesirable tastes and tenderize the protein. Using herbs and spices, such as basil, oregano, and garlic powder, can enhance the aroma and flavor complexity of a dish.
Tart or acidic foods like lemonade, citrus fruits, or pickles may stimulate the taste buds and help clear metallic tastes, though these should be avoided if mouth sores are present. Many patients find that consuming foods at room temperature or colder reduces the intensity of smells, which helps if odors contribute to taste aversion.
Maintaining excellent oral hygiene is important, as brushing and rinsing before and after meals can eliminate lingering bad tastes. If red meat tastes overly bitter or metallic, substitute it with alternative protein sources like poultry, eggs, fish, or tofu to ensure adequate nutritional intake. Sucking on sugar-free hard candies with strong flavors like mint or lemon can also temporarily mask unpleasant tastes.
Timeline for Recovery
Chemotherapy-induced taste changes are usually temporary because the body’s cells eventually regenerate. Recovery generally begins shortly after the last treatment session, though the timeline varies significantly among individuals. Taste perception often starts to improve within a few weeks to three months after chemotherapy is completed.
The full return to normal taste function is a gradual process that can take several months, with some people reporting continued improvement for up to a year or more after treatment concludes. The rate of recovery is influenced by the specific chemotherapy drugs used, the total dose received, and whether concurrent radiation therapy was involved. If taste changes persist beyond the expected recovery period, consult with the care team to investigate other potential causes.