Study Links Long-Term COVID Taste Loss to Molecular Defect in Taste Cells
Mar 2nd 2026
A new study reports reduced PLCβ2 mRNA and structural changes in taste buds of some people with persistent taste loss more than a year after COVID-19, providing the first direct cellular evidence for prolonged taste dysfunction.
- Researchers studied 28 non-hospitalized post-COVID patients and found 8 with abnormal taste tests and 11 reporting loss of sweet, bitter and umami tastes.
- Biopsies from 20 participants showed reduced mRNA for PLCβ2, a key signal amplifier in taste receptor cells for sweet, bitter and umami.
- Salty and sour tastes were largely preserved because those receptor cells do not rely on PLCβ2.
- Some patients also showed structural disorganization of taste buds under the microscope.
- The findings offer a cellular explanation for taste loss persisting more than a year in some people, but the study is small and more research is needed to confirm reversibility and treatment options.