EP 1439
1439. Can Smelling THIS Make Your Brain Younger Overnight?
Host Dave Asprey sits down with Dr. Michael Leon, Professor Emeritus of Neurobiology and Behavior at UC Irvine, to explore why your sense of smell may be one of the most overlooked predictors of brain health, memory, sleep quality, and longevity. They break down why the olfactory system has direct access to the brain’s memory and emotional centers, why smell often declines alongside memory after age 60, and why reduced olfactory function has been associated with Alzheimer’s disease, depression, cognitive decline, and increased all-cause mortality. Dr. Leon explains how COVID, chronic congestion, pollution, stress, menopause, and aging can impair smell without people realizing it, and why restoring olfactory input may matter more than most people think. The conversation dives into olfactory enrichment, including research showing dramatic memory improvements in older adults exposed to multiple scents during sleep, why scent variety and novelty matter for neuroplasticity, and how nighttime smell stimulation may increase deep sleep, improve dreams, and reduce nightmares. They also discuss emerging applications for dementia, PTSD, depression, and autism, why professional wine tasters may offer clues about protecting the aging brain, and how smell connects with GLP-1 drugs, exercise, rapamycin, spermidine, oxytocin, hormones, mitochondrial function, and other longevity interventions. Essential listening for anyone serious about memory, sleep, brain aging, Alzheimer’s prevention, neuroplasticity, smell training, longevity, and protecting cognitive performance as you age.
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In this Episode of The Human Upgrade™...
Your sense of smell may reveal more about your brain health than you realize, and stimulating it while you sleep may improve memory, sleep quality, and cognitive function.
Visit https://memoryair.com/ and use code DAVE15 for 15% off.
Host Dave Asprey sits down with Dr. Michael Leon, Professor Emeritus of Neurobiology and Behavior at UC Irvine and one of the world’s most cited scientists, to explore why smell may be one of the most overlooked tools for brain health and longevity.
Dr. Leon explains why the olfactory system has unusually direct access to the brain’s memory and emotional centers, why smell often declines alongside memory after age 60, and why reduced olfactory function has been associated with Alzheimer’s disease, cognitive decline, depression, and increased all-cause mortality. They also discuss how COVID, chronic congestion, pollution, stress, and aging can impair smell without people realizing it.
The conversation dives into olfactory enrichment, including research showing major improvements in memory when older adults were exposed to multiple scents during sleep. Dr. Leon explains why novelty matters, how nighttime scent exposure may increase deep sleep and reduce nightmares, and why olfactory stimulation is being studied in dementia, PTSD, depression, and autism. Dave also explores connections between smell, GLP-1 drugs, exercise, rapamycin, spermidine, oxytocin, hormones, mitochondrial function, and other longevity interventions.
This is essential listening for anyone interested in memory, sleep, Alzheimer’s prevention, brain aging, smell training, dementia, PTSD, autism, longevity, neuroplasticity, biohacking, and protecting cognitive function as you age.
You’ll Learn:
-Why your sense of smell often declines alongside memory
-How smell connects directly to the brain’s memory and emotional centers
-Why poor olfactory function is associated with Alzheimer’s risk and mortality
-How chronic congestion may affect memory and brain health
-What COVID-related smell loss may mean for long-term cognitive health
-How olfactory enrichment can stimulate memory centers while you sleep
-Why one study reported a 226% improvement in memory in healthy older adults
-How scent exposure may increase deep sleep and reduce nightmares
-Why novelty and rotating scents appear to matter for neuroplasticity
-How smell training is being studied in dementia, depression, PTSD, and autism
-Why several longevity interventions are also associated with improved olfaction
-How GLP-1 drugs may affect smell, food enjoyment, memory, and emotion
-Why professional wine tasters may offer clues about protecting the aging brain
Keywords: Michael Leon, smell training, olfactory enrichment, sense of smell, memory improvement, brain aging, Alzheimer’s disease, dementia, deep sleep, nightmares, PTSD, autism, depression, COVID smell loss, olfactory system, neuroplasticity, MemoryAir, essential oils, cognitive decline, all-cause mortality, GLP-1, rapamycin, spermidine, oxytocin, longevity, brain health, sleep optimization, memory loss, olfactory stimulation
Resources:
- Visit https://memoryair.com/and use code DAVE15for 15% off.
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“The sense of smell has the only direct superhighway access to the memory centers and emotional centers of the brain.”
Michael Leon
0:00 — Smell and Your Brain
Dr. Michael Leon explains why smell has unusually direct access to the brain’s memory and emotional centers, and why losing olfactory input may accelerate cognitive decline.
1:25 — Intro
Dave introduces Dr. Leon, his background in neurobiology, and why smell may be one of the most overlooked tools in brain health and biohacking.
6:52 — Why Smell Goes Unnoticed
They discuss why people often fail to notice gradual smell loss, how aging, COVID, congestion, pollution, stress, and disease can impair olfaction, and why that matters for memory.
10:59 — Making MemoryAir
Dr. Leon explains how nighttime olfactory enrichment works, why multiple scents and novelty matter, and how the MemoryAir device was designed to automate that stimulation during sleep.
15:46 — Smell and Dementia
They explore the connection between olfactory loss and Alzheimer’s disease, how smell training may support memory, and why professional wine tasters offer an interesting model of long-term olfactory enrichment.
20:00 — Smell Predicts Lifespan
Dr. Leon explains why smell ability in middle age is associated with all-cause mortality and discusses the surprising overlap between improved olfaction and several longevity interventions.
25:32 — Testing Your Sense of Smell
Dave and Dr. Leon discuss scratch-and-sniff tests, odor thresholds, scent discrimination, and how people can objectively measure their olfactory function.
28:33 — Autism and Olfactory Therapy
Dr. Leon shares research on environmental enrichment and olfactory stimulation in children with autism, including potential effects on sleep, behavior, and brain function.
36:23 — Biohacking Your Nose
They explore ways to support olfactory function, including smell training, clearing chronic congestion, near-infrared light, exercise, hormones, and other longevity-related interventions.
42:50 — GLP-1 and Olfaction
Dr. Leon discusses conflicting reports on how GLP-1 drugs affect smell and why reduced olfactory function could have downstream effects on memory, emotion, and potentially longevity.
45:55 — PTSD, Nightmares, and Sleep
They examine how olfactory stimulation during sleep may improve deep sleep, make dreams more pleasant, and reduce nightmares, including a striking example involving a veteran with PTSD.
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