The loss of smell and taste soon became one of the signs that warned of the possibility of having contracted COVID-19, especially in the case of those people who did not show any other symptoms. Furthermore, many of those affected did not recover this sense after overcoming the coronavirus infection, and it is even considered one of the symptoms of persistent COVID. In addition, the inability to perceive odors has also been associated with degenerative diseases, such as Parkinson’s or Alzheimer’s.
Now, researchers at the Charlie Dunlop School of Biological Sciences at the University of California Irvine (UC Irvine), in collaboration with the Oxford Humanities Research Center, have discovered a powerful connection between the loss of smell and inflammation in no less than 139 medical conditions.
The results of this study, led by Professor Emeritus Michael Leon along with researchers Cynthia Woo and Emily Troscianko, have been published in the journal Frontiers in Molecular Neuroscience and highlight a little-known but potentially crucial relationship: the role played by the sense of smell in the maintenance of physical and mental health.
Therapeutic stimulation of smell to prevent diseases
Olfactory dysfunction, often overlooked as a minor annoyance, may actually be an early sign of various neurological and organic diseases, this research suggests. “The data are especially interesting because we had previously found that olfactory enrichment can improve memory by 226% in the case of older adults,” Leon stated in a note published at UC Irvine.
“We now know that pleasant aromas can reduce inflammation, suggesting a possible mechanism by which these aromas can improve brain health,” he adds, highlighting that this discovery could have important implications for mitigating symptoms and even reducing the occurrence of certain diseases through therapeutic stimulation of smell.
The study focuses on the detailed analysis of 139 medical conditions associated with olfactory loss and increased inflammation, revealing a possible shared pathway between these factors. Loss of smell, which often precedes diseases such as Alzheimer’s and Parkinson’s, could serve as an early indicator of the onset of these diseases, allowing for more proactive therapeutic approaches.
“We now know that pleasant aromas can decrease inflammation, suggesting a possible mechanism by which these aromas can improve brain health.”
“It was difficult to locate studies for so many medical conditions,” León said, referring to the complexity of linking olfactory loss to such a wide variety of disorders. This challenge, he added, highlights the importance of these findings when considering olfactory health as an integral part of general well-being.
By showing how olfactory enrichment can reduce inflammation, this research lays the foundation for future studies exploring the therapeutic use of aromas in a broader range of medical conditions. “It will be interesting to see if we can improve symptoms of other medical conditions through olfactory enrichment,” Leon said.
As science continues to uncover the profound impact our senses have on health, this research underscores the need to further study olfactory therapies. For this reason, Leon is currently developing, together with Woo, a device to deliver olfactory therapies, which could represent a novel, non-invasive approach to improving health.
