For many people undergoing cancer treatment, food can suddenly taste different or even unpleasant. A new study offers a clearer explanation for why that happens and how it may affect eating.
Researchers found that a class of cancer drugs called tyrosine kinase inhibitors may change the types of cells inside taste buds, reducing the ability to taste sweetness while increasing sensitivity to bitter and savory flavors. The findings, published in Development, help explain a common side effect known as dysgeusia, or taste distortion.
“If you lose the sweet component of everything you eat, your entire sense of taste becomes distorted,” said senior author Linda Barlow, professor of cell and developmental biology at the University of Colorado Anschutz.
The study was conducted using mouse models and lab-grown taste tissue to examine how one of these drugs, cabozantinib, affects taste at a cellular level. Researchers found that the total number of taste buds did not decrease. Instead, the balance of cells within them shifted.
Cells that detect sweet flavors became less common, while cells responsible for detecting bitter and savory tastes increased. This change was linked to the drug’s effect on a protein called KIT, which plays a role in how taste cells develop.
When KIT was blocked, sweet-sensing cells did not form as expected, and other types of taste cells took their place. This shift altered how flavors were perceived, even though the structure of the taste buds remained intact.
“Nothing tastes good to them so they withdraw and become isolated. Isolation leads to depression,” Barlow said, describing how taste changes can affect patients’ daily lives.
Taste changes are often considered a minor side effect, but they can have meaningful consequences. Researchers note that between 10% and 50% of patients taking these medications report altered taste, which can lead to reduced appetite, weight loss and difficulty maintaining proper nutrition.
“People don’t eat and they lose weight. This sometimes leads us to reduce or interrupt the dose of their drugs,” said co-author Elaine Lam, professor of medicine and medical oncology at the CU Anschutz Cancer Center.
The findings may help guide future efforts to reduce or prevent these side effects. Researchers suggest that it may be possible to develop treatments that protect taste function or design drugs that avoid interfering with the KIT protein.
The study was conducted in animal models, and researchers say further work is needed to confirm how these mechanisms apply in people. Still, the results offer a clearer biological explanation for a common experience and highlight how changes in taste can influence eating during illness.
This study was funded by the National Institutes of Health and supported by the University of Colorado.