Losing the ability to smell peppermint, fish, orange, rose and leather could be an accurate early warning sign of dementia, a new study found. It was a long-term study with participation of nearly 3,000 adults, aged 57 to 85. The researchers used a tool known as "Sniffin'Sticks."
These look like a felt-tip pen, but instead of ink, they are infused with distinct scents. Five years after the initial test, almost all of the study subjects who were unable to name a single scent had been diagnosed with dementia. Experts even say “smell testing would be a useful tool for predicting the onset of dementia”. But the test is only a warning signal. It could help find people who are at risk.
Researchers used Sniffin'Sticks
“These results show that the sense of smell is closely connected with brain function and health,” Professor Jayant Pinto, of Chicago University, said. “"Loss of the sense of smell is a strong signal that something has gone wrong and significant damage has been done. We need to understand the underlying mechanisms so we can understand neurodegenerative disease and hopefully develop new treatments and preventative interventions,” he added. Previously, in a 2014 study, olfactory dysfunction was associated with increased risk of death within five years. The olfactory nerve is the only cranial nerve directly exposed to the environment. The cells that detect smells connect directly with the olfactory bulb at the base of the brain. Loss of the sense of smell was a better predictor of death than a diagnosis of heart failure, cancer or lung disease.