Loss of smell has been linked to more than 100 diseases in new research

Researchers from the Charlie Dunlop School of Biological Sciences, working with the Oxford Research Center in the Humanities, reveal a powerful link between smell loss and inflammation in a whopping 139 medical conditions. This study – led by Professor Emeritus Michael Leon and researchers Cynthia Woo and Emily Troscianko – highlights a little-known but potentially life-changing connection: the role our sense of smell plays in maintaining our physical and mental health.

The study appears in Frontiers in molecular neuroscience.

Olfactory disorders, often dismissed as a minor inconvenience, can actually be an early sign of several neurological and physical diseases, as this study shows.

“The data is particularly interesting because we had previously found that olfactory enrichment can improve memory in older adults by 226%,” says Leon. “We now know that pleasant scents can reduce inflammation, potentially pointing to the mechanism by which such scents can improve brain health.”

This finding, he added, could have important implications for alleviating symptoms and possibly even reducing the onset of certain diseases through therapeutic olfactory stimulation.

The study delves into methodically tracking 139 medical conditions linked to both loss of smell and increased inflammation, revealing insights into a shared pathway connecting these factors. Loss of smell, which often precedes conditions such as Alzheimer’s and Parkinson’s disease, can serve as an early indicator of disease onset, allowing for more proactive therapeutic approaches.

“It was difficult to track down the studies for so many medical conditions,” Leon said, reflecting on the complexities of linking smell loss to such a wide range of conditions. The challenge, he added, underscores the importance of these findings in framing olfactory health as an integral part of overall well-being.

By showing how olfactory enrichment can soothe inflammation, this research has laid a foundation for future studies aimed at exploring the therapeutic use of scent to address a broader range of medical conditions.

“It will be interesting to see if we can alleviate the symptoms of other medical conditions with olfactory enrichment,” Leon said.

Together with Woo, Leon is now working on an olfactory therapy device, which could hold promise as a new, non-invasive way to improve health outcomes.

As science continues to discover the profound impact of our senses on health, this study underlines the critical need for further research into olfactory therapies.