With aging comes change; wrinkles, gray hair, and height differences are all a part of the mix. But it’s not just the cosmetic transformations that people fear. According to a study from the Global Brain Health Institute, an international initiative focused on improving brain health and reducing the global impact of dementia, more than half of respondents are afraid of losing their memory. But the solution to memory loss could be hiding right beneath our noses—literally.
Renowned neuroscientist Michael Leon, PhD, knows this firsthand. The former University of California, Irvine professor has spent his career trying to understand how different chemicals alter perception, which eventually led him to study the olfactory system, or the sensory network that controls your sense of smell. Leon’s work shows that you can actually hack your olfactory system to boost memory by more than 200 percent. And the possibilities don’t end there—olfactory enrichment could help students learn more effectively and even stave off Alzheimer’s disease and dementia.
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Go Down the Rabbit Hole With Us
Your nose’s superpower is thanks to a “superhighway” that leads directly into your brain. The olfactory system runs straight to the hippocampus, or your memory hub, whereas other sensory systems have been rerouted throughout our evolution. This means you’re subconsciously accessing a deep part of your brain with just a sniff.
To explain the connection between this superhighway and memory, Leon references sommeliers. Over years of studying to become experts, aspiring sommeliers, or wine stewards, smell thousands of different wines, memorizing the unique aroma and notes of each. Just by practicing their craft, these students are constantly stimulating their olfactory system—and significantly boosting their memory in the process. In fact, one 2016 study published in the journal Frontiers in Human Neuroscience found that the regions of the brain associated with memory are thicker in master sommeliers’ brains compared to the average person.
The researchers on the 2016 study argue that their findings are especially remarkable, as they may suggest that sommeliers are more resistant to neurodegenerative diseases, like Alzheimer’s. Alzheimer’s causes neurons in the brain to stop communicating and eventually die off. At first, Alzheimer’s affects regions of the brain associated with memory, including the hippocampus. So, if the sommeliers have a thicker memory center, there is literally more brain to defend against neuron death.
In his own work, Leon wanted to test the effectiveness of olfactory stimulation among different populations. For instance, Leon and his colleagues conducted a study on a group of 43 men and women, all between the ages of 60 to 85, which falls within the age range when memory loss becomes a concern, according to experts. The participants were given odor diffusers to use each night over the course of the study. Half of the participants were exposed to an array of essential oils, and the other half to a placebo with “trace amounts of odorant,” according to the paper, which was published in Frontiers in Human Neuroscience in 2023.
Participants’ memories were tested before the experiment and again after six months. They found that the scent-enriched group’s memory—or the group who received olfactory stimulation each night—improved by a whopping 226 percent, compared to the group which received no stimulation. Again, this is likely thanks to the olfactory system acting as a superhighway to the memory center of the brain. According to Leon, this was “the largest improvement in memory that anyone has found.”
In a later paper published in Frontiers in Molecular Neuroscience, Leon and his colleagues further underscored the impact of the olfactory system on brain health. The team observed a relationship between olfactory decline, or the loss of smell, and 139 neurodegenerative conditions including Alzheimer’s and dementia. That means olfactory stimulation can help the brain, but olfactory deprivation can be detrimental
These findings are particularly concerning, as many people who contracted COVID-19 permanently lost some or all of their sense of smell. According to a 2023 study published in the journal Laryngoscope, 24 percent of patients who experienced smell loss from COVID only partially recovered their sense of smell, and 3 percent saw no improvement.
Luckily, not all hope is lost for those who may have dampened senses of smell.
“Olfactory enrichment, getting multiple odors on a regular basis, can help people restore their ability to
smell things,” Leon says. He explains that, even without your sense of smell, the hardware for smelling—or the neurons and receptors—is still there, and stimulating those faulty wires might naturally reboot them.
In other words, you may be able to rebuild your olfactory system from the ground up, even if you can’t initially identify the aromas you’re being exposed to. Traditional smell retraining therapy (SRT) requires daily exercises in which patients have to inhale several scents, and it often takes months to see results. However, there may be more practical, everyday activities that could stimulate your olfactory system. For example, one recent study found that enrolling patients with olfactory dysfunction in frequent cooking classes could be more effective than typical SRT when it comes to reviving the sense of smell.
And olfactory stimulation isn’t just for those looking to fend off memory loss; Leon says that olfactory stimulation may help younger populations, too. He and his colleagues believe that olfactory stimulation may be closely tied to students’ executive function, “which is flexible intelligence, the ability to focus on things attentionally, and the ability to inhibit inappropriate behaviors—just what you need to succeed in school,” according to Leon. But he concedes that more work needs to be done before they can conclude that olfactory stimulation “may be a way to improve outcomes for educational abilities.”
Your sense of smell is a biological superpower, ready to boost memory. But do we have to sniff everything we come into contact with—to literally stop and smell the roses—in order to see results? Leon admits that this is deeply impractical, so he came up with a convenient solution.
Earlier this year, Leon and his team launched a product called Memory Air, which provides olfactory stimulation for users. Similar to his groundbreaking 2023 study, the device releases aromas for the user to inhale throughout the night. Memory Air cycles through 40 pleasant-smelling odors, which the team believes is a crucial part of its success. Leon explains that the scents don’t serve individual purposes like they would in an aromatherapy practice; instead, the wide variety better stimulates the olfactory system and, thus, the brain. The product is available on the Memory Air website for $799, with additional subscriptions available to refill the scent band insert.
Emma Frederickson graduated from Pace University where she studied communication and media. Prior to her time as an editor, she was a freelance science reporter. She enjoys covering everything from shipwrecks to pimple popping, but her favorite topics include climate change, conspiracy theories, and weird biology. When she’s not writing, Emma can be found hopping between coffee shops on the hunt for the world’s best oat milk cappuccino.