By james art Irvine, California, October 29, 2024 — Researchers from the Charlie Dunlop School of Biological Sciences, in collaboration with the Oxford Humanities Research Centre, have revealed a strong link between loss of smell and inflammation in a staggering 139 medical conditions. This research—led by Professor Emeritus Michael Leon and researchers Cynthia Wu and Emily Troshianko—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 dysfunction, often dismissed as a minor inconvenience, can actually be an early sign of a variety of neurological and physical ailments, as indicated by this research. “The data is particularly interesting because we previously found that smell can improve older people’s memory by 226 percent,” Leon said. “We now know that pleasant aromas can reduce inflammation, potentially pointing to a mechanism by which such aromas can improve brain health.”
This finding, he added, could have key implications for alleviating symptoms and possibly even reducing the onset of certain diseases through therapeutic olfactory stimulation.
The study delved into the methodical tracking of 139 medical conditions associated with both loss of smell and increased inflammation, revealing insights into a common pathway linking these factors. The loss of smell, which often precedes conditions such as Alzheimer’s and Parkinson’s diseases, can serve as an early indicator of the onset of the disease, allowing for more proactive therapeutic approaches.
“It’s been difficult to keep track of studies for so many medical conditions,” Leon said, reflecting on the complexity of linking olfactory loss to such a wide range of diseases. The challenge, he added, underscores the importance of these findings in defining olfactory health as an integral part of overall well-being.
By showing how olfactory enrichment can moderate inflammation, this research sets the stage for future studies aimed at exploring the therapeutic use of aroma to address a wider range of medical conditions. “It will be interesting to see if we can improve the symptoms of other medical conditions with olfactory enrichment,” Leon said.
Together with Woo, Leon is now working on an olfactory therapy delivery device that may hold promise as a new, non-invasive way to improve health outcomes.
As science continues to uncover the profound effects of our senses on health, this research underscores the critical need for further research into olfactory therapies.
About the University of California, Irvine Charlie Dunlop School of Biological Sciences:
Recognized for its pioneering research and academic excellence, the Charlie Dunlop School of Biological Sciences has been instrumental in the university’s status among the nation’s top 10 public universities, as ranked by US News & World Report. It offers a wide range of educational programs in the life sciences, fostering innovation and preparing students for leadership in research, education, medicine and industry. Nestled in a globally recognized and economically vibrant community, the school contributes to the university’s influence as Orange County’s largest employer and a significant economic contributor. Through its commitment to exploring the complexities of life, the Dunlop School embodies UCI’s legacy of innovation and societal impact. For more information about the Charlie Dunlop School of Biological Sciences visit
About the University of California, Irvine: Founded in 1965, UC Irvine is a member of the prestigious Association of American Universities and is ranked among the nation’s top 10 public universities by US News and World Report. The campus has produced five Nobel laureates and is known for its academic excellence, world-class research, innovation and mascot anteater. Led by Chancellor Howard Gilman, UC Irvine has more than 36,000 students and offers 224 degree programs. Located in one of the safest and most economically vibrant communities in the world, it is the second largest employer in Orange County, contributing $7 billion annually to the local economy and $8 billion to the statewide economy. For more information about UC Irvine, visit www.uci.edu.
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UC Irvine’s Bright Futures Campaign: Publicly launched on October 4, 2019, the Brilliant Future campaign aims to raise awareness and support for UC Irvine. By engaging 75,000 alumni and raising $2 billion in philanthropic investment, UC Irvine strives to reach new heights of excellence in student success, health and wellness, research and more. The Charlie Dunlop School of Life Sciences played a vital role in the success of the campaign. Learn more by visiting