Publication date: Sep 26, 2025
People who suspect that their sense of smell has been dulled after a bout of COVID-19 are likely correct, a new study using an objective, 40-odor test shows. Based on the results, smelling ability was characterized as normal, mildly impaired, moderately impaired, severely impaired, or lost altogether. Those with a diminished sense of smell may also struggle to detect dangers such as spoiled food, gas leaks, and smoke, experts say. “These results suggest that health care providers should consider testing for loss of smell as a routine part of post-COVID care,” said Horwitz. “Experts are now exploring ways to restore smelling ability after having COVID-19, such as vitamin A supplementation and olfactory training to “rewire” the brain’s response to odors. In this scratch-and-sniff evaluation, which is considered the gold standard of its kind, participants were asked to identify 40 scents by selecting the right multiple-choice option for each odor. “While patients may not notice right away, a dulled nose can have a profound impact on their mental and physical well-being.
| Concepts | Keywords |
|---|---|
| Alzheimer | Ability |
| Arizona | Clinical |
| Miami | Covid |
| Pennsylvania | Horwitz |
| Impaired | |
| Md | |
| Mph | |
| Olfactory | |
| Participants | |
| Phd | |
| Sense | |
| Smell | |
| Smelling | |
| Team | |
| Test |
Semantics
| Type | Source | Name |
|---|---|---|
| disease | MESH | Parkinson’s disease |
| disease | MESH | Alzheimer’s disease |
| disease | IDO | symptom |
| disease | MESH | coronavirus infection |
| drug | DRUGBANK | Gold |
| drug | DRUGBANK | Vitamin A |
| disease | MESH | loss of taste |
| drug | DRUGBANK | Methylphenidate |
| disease | MESH | Long Covid |
| disease | MESH | neurodegenerative disorders |
| disease | MESH | COVID-19 |
| disease | IDO | country |
| disease | MESH | causes |
| disease | MESH | hyposmia |
| disease | IDO | history |
| disease | MESH | weight loss |
| disease | IDO | quality |
| disease | MESH | depression |