Ep.79, The Hidden Connection Between Smell, Sleep & Neurodegeneration, Dr. Paule Valery Joseph

What if your sense of smell could predict brain health years before symptoms appear? In this fascinating episode of ASAP Pathway the Podcast, Dr. Stacy Becker sits down with neuroscientist and sensory science expert Dr. Paule Valery Joseph to explore the powerful — and often overlooked — role of smell, taste, and chemesthesis in human health.

From Alzheimer’s and Parkinson’s disease to sleep-disordered breathing, childhood mouth breathing, long COVID, and emotional memory, this conversation uncovers how deeply connected our olfactory system is to neurological health, cognition, metabolism, and quality of life. Dr. Joseph explains why smell loss may be one of the earliest warning signs of neurodegenerative disease, how COVID changed the medical conversation around smell and taste, and why clinicians should begin treating smell as a vital sign.

The discussion also dives into:

• Mouth breathing and nasal disuse in children
• Sleep apnea and olfactory dysfunction
• Smell training and neuroplasticity
• The emotional power of scent and memory
• Why dentists may be key players in early detection
• The hidden consequences of congenital anosmia

This episode is a powerful reminder that the body does not function in silos — and that the nose may hold far more information about our health than we ever realized.


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Website: paulejoseph.bio


Chapters 📖
00:00 – Introduction to Dr. Polly Valerie Joseph
02:23 – What Is Chemesthesis?
04:24 – How Smell & Taste Affect Metabolic and Brain Health
07:51 – The Story That Revealed Smell as a Warning Sign
09:18 – Why Doctors Rarely Test Cranial Nerve One
12:14 – When Smell Loss Should Concern You
14:13 – Why Smell Should Be Considered a Vital Sign
16:42 – The Connection Between Smell & Neurodegenerative Disease
20:09 – Early Warning Signs of Smell Dysfunction
22:01 – COVID, Mouth Breathing & Loss of Smell
23:43 – Cognitive Effects of Smell Loss
26:15 – The Importance of Cooking, Flavor & Sensory Engagement
27:20 – Post-COVID Smell Recovery Clinics & Smell Training
28:34 – Olfactory Training and Neuroplasticity
32:10 – Why Most People Would Give Up Their Sense of Smell
33:40 – Smell, Memory & Emotional Connection
35:33 – Mouth Breathing, Kids & Long-Term Brain Development
39:50 – Sleep Apnea, CPAP & Olfactory Function
48:10 – Sleep, Smell & Brain Activity
52:21 – Smell Loss as an Early Sign of Neurodegeneration
55:00 – Questions Dentists Should Start Asking Patients
59:56 – The Body as an Interconnected System
01:02:24 – Dr. Joseph’s Upcoming Book “Common Sense”
01:05:29 – The Smell & Taste Association of North America
01:06:13 – Congenital Anosmia Explained
01:08:06 – Ben & Jerry’s and the Science of Flavor Texture
01:11:54 – Final Thoughts & Future Collaboration

Learnings 📚

• Smell is directly connected to the limbic system, linking scent to memory and emotion.
• Loss of smell may appear 10–15 years before obvious signs of neurodegenerative disease.
• Smell dysfunction can affect cognition, nutrition, emotional health, and quality of life.
• COVID highlighted how critical smell and taste are to everyday human functioning.
• Mouth breathing and poor nasal function in children may have broader neurological implications than previously understood.
• Sleep-disordered breathing and intermittent hypoxia may impact olfactory processing and brain health.
• Smell training can help stimulate neuroplasticity and recovery after smell loss.
• Dentists may play an important role in identifying smell dysfunction during routine evaluations.
• Congenital anosmia affects more than flavor perception — it may also influence safety, social connection, and emoti