Study estimates millions did not fully recover sense of taste or smell after COVID

A new study from Mass Eye and Ear estimates that millions of Americans did not fully recover their sense of taste or smell after contracting COVID.

The study found that 60% of people lost some ability to taste and smell during a COVID infection in 2021, and a quarter of those patients didn't fully recover those senses. An estimated 28 million Americans were left with a decreased sense of smell after having COVID.

Dr. Neil Bhattacharyya, a professor of otolaryngology at Mass Eye and Ear and the lead researcher on the study, said he was inspired to look into the data after seeing patients who lost weight or had a change in eating habits after losing their sense of taste or smell.

Bhattacharyya and fellow researchers pulled data from the National Health Interview Survey, an annual report from the Centers for Disease Control and Prevention that asks participants a range of questions about their overall health. In 2021, the CDC added survey questions about COVID, including about the loss of taste or smell, which researchers used for their analysis.

Researchers found that of the people who lost their sense of smell, 24% only partially recovered and over 3% had no recovery of the sense at all. Similarly, 20% of people who lost their sense of taste only partially recovered, and over 2% did not recover at all.

The study examined only data from 2021, so those who recovered the sense after the year or the impacts of different COVID variants that emerged later are not documented in the study.

Bhattacharyya said he was surprised to learn both how many people lost the senses during their initial infection, and how many people still haven't fully recovered.

"From a national health perspective, I mean, we have millions of people without their sense of smell," said Bhattacharyya. "What does that mean for detecting a gas leak? What does it mean for detecting rancid food, smelling a soiled diaper? There's going to be a lot of quality of life impact, I think, down the line for this."

For those who lost their ability smell or taste, Bhattacharyya said there are treatments, like smell retraining therapy, that are somewhat effective in helping people regain their senses. He said that some trials for treatment are underway as health professionals are "starting to realize the magnitude of this problem."

But Bhattacharyya said the longer it has been since the initial loss of sense, the harder may be to get it back.