Stopping to smell the roses really does improve the health of older people, according to a study conducted by researchers at University of California, Irvine.
Researchers said their study transforms a long-known tie between smell and memory into an easy, noninvasive technique for strengthening memory and potentially deterring dementia.
“The general idea is that when humans don’t get enough olfactory stimulation, the memory centers of their brains start to deteriorate,” Michael Leon, one of the study’s authors and a UCI professor of neurobiology and behavior, told the Business Journal.
“This deterioration looks like it can be reversed with olfactory enrichment.”
The team’s study, which appeared in Frontiers in Neuroscience, has already reached the top 40 neurology papers ever published, as ranked by Altmetrics.
“The data is more convincing and stronger than any of the drugs that have been developed for dementia,” Leon said.
The scientists have formed a company, Memory Air, that’s raised $8 million and is planning to start selling a product this fall that will release 40 odors twice a day to improve the memories of older adults.
Scientists have long known that the loss of smell can predict the development of nearly 70 diseases, including Alzheimer’s and other dementias.
Researchers have previously found that exposing people with moderate dementia to up to 40 different odors twice a day over a period boosted their memories and language skills, eased depression and improved their olfactory capacities.
The UCI team decided to experiment with a noninvasive dementia-fighting tool.
“The reality is that over the age of 60, the olfactory sense and cognition starts to fall off a cliff,” Leon said.
The project, which was funded by Procter & Gamble, was conducted through the UCI Center for the Neurobiology of Learning & Memory.
About 43 men and women, aged 60 to 85 without memory impairment, were given a diffuser and seven cartridges, each containing a single and different natural oil.
People in the enriched group received full-strength cartridges. Control group participants were given the oils in tiny amounts. The odors included rose, eucalyptus, lemon and lavender.
“By making it possible for people to experience the odors while sleeping, we eliminated the need to set aside time for this during waking hours every day,” said Cynthia Woo, the study’s lead author.
The study didn’t determine if any fragrance was more effective than others.
People in the enriched group showed a 226% increase in cognitive performance compared to the control group, as measured by a word list test commonly used to evaluate memory.
“More emphasis should be placed on treating the loss of smell,” said Michael Yassa, a UCI professor who is also director of the UCI neurobiology center.
“Everyone has experienced how powerful aromas are in evoking recollections, even from very long ago,” he said. “However, unlike with vision changes that we treat with glasses and hearing aids for hearing impairment, there has been no intervention for the loss of smell.”