Adam’s Journal
On the heels of my last bout of Covid, things that used to taste good tasted bad or, sometimes, like not much at all. I know that loss of taste is a side effect of Covid, but should I worry? Could this signal other health issues?
Dr. Scofield Prescribes
Covid is known to cause changes in taste, and they can linger even after other symptoms have resolved. These changes are known technically as ageusia (loss of taste) and dysgeusia (when foods taste distorted or unpleasant).
While you may think of the sensation as a loss of taste, what’s actually happening involves smell: Much of what we perceive as taste is actually aromas traveling into the nose, where we have about 400 different smell receptors. A 2024 study in the journal Science calculated that we can distinguish 1 trillion different smells.
However, upper respiratory infections – not only Covid, but also flu, colds and sinusitis – can disrupt these receptors. When this happens, foods can taste flat, muted or simply bad.
Happily, for most people, this disruption is only temporary, with normal smell and taste returning within weeks or months. In some, recovery can take longer.
If the issue persists, grows worse or is accompanied by other symptoms – especially neurological ones – you should discuss it with your physician. Although it seems highly unlikely in your situation, there is evidence that a loss of smell can be an early warning sign for dementia.
In a recent study, scientists followed 900 people with a gene called ApoE4, which carries an increased risk of Alzheimer’s, for a decade. They found these people experienced a more rapid decline in smell than those without the gene. (We all lose some ability to smell as we age.) And other studies have found that a loss of the sense of smell can precede many forms of dementia.
A change in or loss of smell or taste can also signal other diseases. Approximately 10% of patients with severe kidney disease will experience a severe or total loss of smell, and roughly half of all others will have smaller changes.
In rare cases, altered senses of taste and smell can even herald an undiagnosed cancer.
For you, I wouldn’t worry. With your recovery from Covid, I expect that – if it hasn’t already – your sense of taste will return to normal. Just give it time.
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Dr. Hal Scofield is a physician-scientist at the Oklahoma Medical Research Foundation, and he also serves as Associate Chief of Staff for Research at the Oklahoma City VA Medical Center. Adam Cohen is OMRF’s senior vice president and general counsel. Send your health questions to contact@omrf.org.
