Study Reveals Why COVID Affects Your Sense Of Taste

Over the past two years of life in the time of COVID-19, we have learned a lot about what to look out for as far as symptoms go. Allergy sufferers have swabbed their noses endlessly in fear that seasonal sniffles are something more, and bland food gets a hot sauce hit just to ensure that our taste buds are still working. According to Harvard Health Publishing, losing our sense of smell and taste is a telltale sign of infection. A recent study sheds some light on how coronavirus affects our olfactory senses, which, in turn, disrupts our ability to taste food.

Science World explains that our sense of taste is limited to five flavors: sweet, sour, umami, salt, and bitter. Flavor notes that amplify those five core tastes are experienced through our sense of smell. Researchers tested this theory by plugging volunteers' noses while they tasted various foods and showed that when their nasal passages were blocked, their sense of taste was greatly diminished. They concluded that 80% of what we taste could be attributed to our sense of smell.

Anosmia, the medical term for losing the sense of smell, is a symptom of many garden-variety respiratory infections. We've all had a stuffy nose that made food taste pointlessly bland, but it's an annoying symptom that is usually mild and clears up quickly. A study conducted by Cell looked at humans and hamsters infected with COVID-19 in an attempt to discover why, exactly, coronavirus leads to a loss of smell and taste in some patients.

Why COVID causes many people to lose their sense of taste

While a stopped-up nose from the common cold or flu can lead to a lessened sense of smell and taste, Prevention notes that many people experiencing anosmia due to a COVID-19 infection did not have nasal congestion. This anomaly prompted researchers to study the neurological symptoms experienced by COVID patients as they relate to olfactory dysfunction (via Cell).

Researchers initially believed that COVID directly affected olfactory sensory neurons, the nerve cells that detect odors and transmit that information to the central nervous system (via NCBI). Further analysis showed that what's actually being affected are the cells that line our nasal cavity. When an infection causes nasal cells to become inflamed, they can no longer display the nasal receptors that detect odors. As aromas are essential to our sense of taste, losing our sense of smell directly affects our taste buds' ability to process flavor sensations.

For many people experiencing loss of smell and taste due to a COVID infection, symptoms clear up within weeks, but some experience lasting symptoms that can go on for months. Losing the ability to smell and taste is a symptom that can significantly diminish the joys of our favorite flavor combinations, and, unfortunately, there are no current treatments for this side effect. Identifying how COVID affects our sense of smell and taste will hopefully lead researchers to discover more effective therapeutics going forward.