In this episode, Matt delves into the curious and cautionary tale of Delta Sleep-Inducing Peptide (DSIP), once hailed as a potential miracle cure for insomnia. In the 1970s, researchers were on a quest for a single "somnogenic molecule" that could act as the brain's natural sleep switch. A Swiss team believed they had found it, isolating a peptide that appeared to rapidly induce deep, slow-wave sleep when injected into animals. This initial excitement led to bold claims and sparked decades of research into what seemed to be a revolutionary breakthrough in sleep science.

However, the promising discovery soon began to unravel under closer scientific scrutiny. Red flags emerged, including the inability to find the gene that coded for DSIP and the peptide's extreme fragility, which prevented it from effectively reaching the brain. When rigorous, placebo-controlled human trials were finally conducted, the results were profoundly disappointing, showing no significant clinical benefit over a placebo. Ultimately, the story of DSIP serves as a powerful lesson on the dangers of scientific overconfidence, the critical importance of replication and skepticism, and the profound complexity of sleep regulation, reminding us that there is no single "magic bullet" for a good night's sleep.

Please note that Matt is not a medical doctor, and none of the content in this podcast should be considered medical advice in any way, shape, or form, nor prescriptive in any way.

In a supplement industry where trust is critical, Matt uses podcast partner Puori. Their protein powders are free from hormones, GMOs, and pesticides, with every single batch third-party tested for over 200 contaminants. For protein you can trust, save 20% at puori.com/mattwalker.

As always, if you have thoughts or feedback you’d like to share, please reach out to Matt:

Matt: Instagram @drmattwalker, X @sleepdiplomat, 

YouTube: https://www.youtube.com/channel/UCA3FB1fOtY4Vd8yqLaUvolg

Matt explores the human capacity for echolocation this week, dismantling the myth that this "biological sonar" is exclusive to animals. Revealing how peer-reviewed research shows all human brains possess the neural hardware to "see" with sound, Matt explains the physics of how sound creates detailed acoustic maps of our environment and introduces the brain's remarkable plasticity, setting the stage for this incredible sensory adaptation.

The episode features stories of pioneers like Daniel Kish, who use echolocation to navigate with astonishing precision. Matt discusses groundbreaking studies from UC Berkeley and Durham University, where brain scans revealed the visual cortex rewires itself to process sound as spatial information. This evidence proves echolocation is not a rare gift but a learnable skill, forcing a reevaluation of the limits of human perception and the brain's adaptive power.

Please note that Matt is not a medical doctor, and none of the content in this podcast should be considered medical advice in any way, shape, or form, nor prescriptive in any way.

As a huge supporter of mission-driven companies, Matt recommends new partner Branch Basics. Their plant- and mineral-based ‘The Concentrate’ is tough on kitchen grease yet gentle enough for baby toys, helping you create a toxin-free home. Get 15% off with code MattWalker at branchbasics.com/mattwalker.

Another partner, AG1, is one that Matt relies upon for his foundational nutrition. Their new science-backed Next Gen formula features upgraded probiotics, vitamins, and minerals. Start your subscription today to get a FREE bottle of Vitamin D3+K2 and 5 free travel packs with your first order at drinkag1.com/mattwalker.

In a supplement industry where trust is critical, Matt uses podcast partner Puori. Their protein powders are free from hormones, GMOs, and pesticides, with every single batch third-party tested for over 200 contaminants. For protein you can trust, save 20% at puori.com/mattwalker.

As always, if you have thoughts or feedback you’d like to share, please reach out to Matt:

Matt: Instagram @drmattwalker, X @sleepdiplomat, 

YouTube: https://www.youtube.com/channel/UCA3FB1fOtY4Vd8yqLaUvolg

While we've long been told to focus on the quantity of our sleep, in today’s episode, Matt suggests a paradigm shift in our understanding of sleep health. He argues that the true cornerstone may not be how many hours we get, but the consistency of our sleep schedule. This concept of regularity - maintaining a stable bedtime and wake-time - is presented as the most impactful of four key sleep components, which also include the more familiar aspects of quantity, quality, and timing.

Matt supports this perspective with findings from a groundbreaking study that objectively tracked the sleep of nearly 90,000 people. The results are stunning: inconsistent sleep rhythms, independent of total sleep time, were linked to a significantly increased risk for a vast array of serious diseases. This research also upends the long-held belief that "too much" sleep is unhealthy. It revealed that many self-proclaimed long sleepers are actually experiencing poor, fragmented sleep, a fact hidden by less reliable self-reported data. The implication is profound: the true culprit for their associated health risks is likely not the extended time in bed, but the underlying lack of a stable, restorative sleep rhythm.

Please note that Matt is not a medical doctor, and none of the content in this podcast should be considered medical advice in any way, shape, or form, nor prescriptive in any way.

One of this week's sponsors, LMNT, offers a science-based electrolyte drink with no sugar or artificial ingredients. Try their new limited-time Lemonade Salt flavor, available May 20th! Get eight free sample packs with any order at drinklmnt.com/mattwalker. Stock up on this summer flavor while it lasts!

Another sponsor, Shopify, made launching Matt's merchandise incredibly smooth with its integrated sales system. Shopify simplifies everything from online stores to in-person sales. Start your exclusive trial and see for yourself at shopify.com/mattwalker.

Our third sponsor this week, David, is a revolutionary new protein bar developed with Dr. Peter Attia. It boasts an unbeatable ratio: 28g of protein and 0g of sugar in just 150 calories. Incredibly satiating with six amazing flavors, it’s perfect for muscle health. Visit davidprotein.com/mattwalker and buy 4 cartons to get a 5th FREE!

As always, if you have thoughts or feedback you’d like to share, please reach out:

Matt: Instagram @drmattwalker, X @sleepdiplomat, 

YouTube https://www.youtube.com/@sleepdiplomatmattwalker9299

Settle in for a deeply comforting experience as Matt returns with a gentle voyage aboard "The Dreamer." This sleep story is crafted to soothe the heart and quiet the mind, creating a perfect sanctuary for rest. Tonight, we journey to a peaceful, seaside village to meet Henry, an elderly widower whose sleepless nights are filled with a profound sense of loss and treasured memories of his late wife, Margaret. 

As Henry steps onto the boat, feeling the weight of his grief begin to soften with the rhythmic sway of the waves, Matt's words paint a picture of a starlit ocean and a secluded, tranquil island, transporting you to a place of healing. As Henry is guided toward a tender reunion and finds the deep, restorative peace that has long escaped him, allow this story to carry you to your own state of profound, restful slumber.

Tired of untrustworthy protein shakes? Show sponsor Puori prioritizes quality: hormone-free, GMO-free, and pesticide-free. Every batch is third-party tested for 200+ contaminants - you can even scan the QR code for lab results! Matt recommends the addictive dark chocolate flavor with 21g of protein. Ready to experience the Puori difference? Matt’s listeners get 20% off, so visit puori.com/mattwalker today!

As always, if you have thoughts or feedback you’d like to share, please reach out to Matt or Eti:

Matt: Instagram @drmattwalker, X @sleepdiplomat, 

YouTube https://www.youtube.com/@sleepdiplomatmattwalker9299

This week, Matt examines the viral trend of mouth taping, a practice touted as a remedy for snoring and sleep apnea. He explains the core theory, which centers on promoting the benefits of nasal over mouth breathing, before critically assessing whether this popular ritual is a scientifically sound solution or a risky trend whose dangers are lost amidst the online hype.

Matt navigates the scientific evidence, revealing a cautionary tale: while preliminary data suggests a potential benefit for a select group with mild obstructive sleep apnea, he sounds a marked alarm for those with moderate to severe conditions. For this latter group, mouth taping can be dangerous, potentially worsening airway obstruction by blocking a necessary escape valve for air. Our host also warns that you must never tape an infant or young child's mouth, and to always skip taping if you have a cold or severe allergies. He concludes that for most, the practice is unproven with unknown long-term safety, and the hype has far outpaced the data, making a cautious approach and professional medical consultation essential.

Please note that Matt is not a medical doctor, and none of the content in this podcast should be considered medical advice in any way, shape, or form, nor prescriptive in any way.

One of our sponsors this week is the biochemical electrolyte drink company LMNT, and they are very kindly offering eight free sample packs when you purchase any one of their orders at drinklmnt.com/mattwalker. LMNT is an electrolyte sports drink that I can get behind - it's created from the basis of science, and it has no sugar, no coloring, and no artificial ingredients – all qualities that are so important to maintaining your blood biochemical balance. And now their new Lemonade Salt is squeezing onto the scene Tuesday, May 20th! This limited-time flavor is here to keep you at your best all summer long, and, just like summer, it’s here for a good time, not a long time, so stock up while supplies last! If you want to give Lemonade Salt or any of the fantastic LMNT flavors a try, just head on over to drinklmnt.com/mattwalker and get your free Sample Pack with your first purchase.

Matt will be the first to tell you that launching his sleep-related merchandise sales was incredibly smooth, thanks to our new sponsor Shopify and their integrated sales and inventory system. And now, just for you,  Shopify is generously offering an exclusive trial at shopify.com/mattwalker. Whether it's online or in-person sales, Shopify simplifies it all. So, be sure to stop in at shopify.com/mattwalker to start your exclusive journey now! 

Matt’s good friend Dr. Peter Attia has helped develop David, a revolutionary new protein bar, and a sponsor of today’s episode! 28g of protein, 0g sugar, only 150 calories – the best ratio EVER! Amazing taste, six flavors, incredibly satiating, and a great source of the protein that helps build muscle, manage metabolic health, and keep you full. Visit davidprotein.com/mattwalker now for an amazing deal: Buy 4 cartons, and get a 5th FREE! . Hurry! Your new favorite protein bar awaits!

As always, if you have thoughts or feedback you’d like to share, please reach out:

Matt: Instagram @drmattwalker, X @sleepdiplomat, 

YouTube https://www.youtube.com/@sleepdiplomatmattwalker9299

In their latest Ask Me Anything episode, Matt and Dr. Eti Ben Simon delve into the complex relationship between common substances and sleep. They first tackle cannabis, explaining that while THC may initially help with sleep onset, its chronic use is detrimental, leading to tolerance, withdrawal insomnia, and a powerful suppression of restorative REM sleep. The discussion then moves to two other major sleep disruptors: caffeine and alcohol. You'll learn how caffeine's long half-life can reduce deep sleep by up to 40% even when consumed in the afternoon, and how alcohol, despite its sedative properties, severely fragments sleep and decimates the quantity and quality of your nightly dream sleep.

The conversation then explores more novel compounds and strategies, starting with a practical bio-hack, the "nappuccino," a precisely timed combination of coffee and a short nap to maximize alertness. From there, the hosts dive into the fascinating world of psychedelics, revealing how drugs like LSD and psilocybin act as potent wake-promoting agents that disrupt sleep before causing a significant "REM sleep rebound" on subsequent nights. They contrast this with ketamine, a dissociative that uniquely increases deep slow-wave sleep, potentially explaining its antidepressant effects. The episode concludes by looking at the intricate and largely unexplored role sleep plays in the therapeutic journey of these powerful psychoactive compounds.

Please note that Matt is not a medical doctor, and none of the content in this podcast should be considered medical advice in any way, shape, or form, nor prescriptive in any way.

Matt will be the first to tell you that launching his sleep-related merchandise sales was incredibly smooth, thanks to our new sponsor Shopify and their integrated sales and inventory system. And now, just for you,  Shopify is generously offering an exclusive trial at shopify.com/mattwalker. Whether it's online or in-person sales, Shopify simplifies it all. So, be sure to stop in at shopify.com/mattwalker to start your exclusive journey now!

Having personally used and purchased AG1 for over four years, Matt encourages you to try the new AG1 Next Gen formula with upgraded probiotics plus additional vitamins and minerals. Backed by 4 human clinical trials demonstrating a boost in healthy gut bacteria, AG1 continuously adapts to the latest science. Subscribe today and receive a FREE bottle of AG D3K2, an AG1 welcome kit, and 5 upgraded AG1 travel packs with your first order. Visit drinkag1.com/mattwalker to learn more and get started on your health journey.

Tired of untrustworthy protein shakes? Show sponsor Puori prioritizes quality: hormone-free, GMO-free, and pesticide-free. Every batch is third-party tested for 200+ contaminants - you can even scan the QR code for lab results! Matt recommends the addictive dark chocolate flavor with 21g of protein. Ready to experience the Puori difference? Matt’s listeners get 20% off, so visit puori.com/mattwalker today!

As always, if you have thoughts or feedback you’d like to share, please reach out to Matt or Eti:

Matt: Instagram @drmattwalker, X @sleepdiplomat, 

YouTube https://www.youtube.com/@sleepdiplomatmattwalker9299

Eti: X @etoosh, Instagram https://www.instagram.com/eti_bensimon/,  or email at [email protected]

Matt welcomes UCSF sleep expert Dr. Aric Prather to the podcast this week to discuss the science of psychoneuroimmunology: the link between our behavior and immune health. After a primer on the immune system’s innate and adaptive arms, Dr. Prather details how insufficient sleep dramatically increases your risk of catching a cold, significantly blunts vaccine effectiveness by reducing antibody response, and promotes a state of chronic, low-grade inflammation - a known pathway to numerous age-related diseases.

Ultimately, the conversation illuminates a profound and actionable truth: sleep is arguably our most powerful, yet tragically overlooked, weapon in the daily battle for immunological health.

Please note that Matt is not a medical doctor, and none of the content in this podcast should be considered medical advice in any way, shape, or form, nor prescriptive in any way.

One of our sponsors this week is the biochemical electrolyte drink company LMNT, and they are very kindly offering eight free sample packs when you purchase any one of their orders at drinklmnt.com/mattwalker. LMNT is an electrolyte sports drink that I can get behind - it's created from the basis of science, and it has no sugar, no coloring, and no artificial ingredients – all qualities that are so important to maintaining your blood biochemical balance. And now their new Lemonade Salt is squeezing onto the scene Tuesday, May 20th! This limited-time flavor is here to keep you at your best all summer long, and, just like summer, it’s here for a good time, not a long time, so stock up while supplies last! If you want to give Lemonade Salt or any of the fantastic LMNT flavors a try, just head on over to drinklmnt.com/mattwalker and get your free Sample Pack with your first purchase.

Matt will be the first to tell you that launching his sleep-related merchandise sales was incredibly smooth, thanks to our new sponsor Shopify and their integrated sales and inventory system. And now, just for you,  Shopify is generously offering an exclusive trial at shopify.com/mattwalker. Whether it's online or in-person sales, Shopify simplifies it all. So, be sure to stop in at shopify.com/mattwalker to start your exclusive journey now! 

Matt’s good friend Dr. Peter Attia has helped develop David, a revolutionary new protein bar, and a sponsor of today’s episode! 28g of protein, 0g sugar, only 150 calories – the best ratio EVER! Amazing taste, six flavors, incredibly satiating, and a great source of the protein that helps build muscle, manage metabolic health, and keep you full. Visit davidprotein.com/mattwalker now for an amazing deal: Buy 4 cartons, and get a 5th FREE! . Hurry! Your new favorite protein bar awaits!

As always, if you have thoughts or feedback you’d like to share, please reach out:

Matt: Instagram @drmattwalker, X @sleepdiplomat, 

YouTube https://www.youtube.com/@sleepdiplomatmattwalker9299

Dr. Aric Prather: https://www.aricprather.com/

Prepare for a tranquil journey into sleep as Matt returns with a voyage aboard "The Dreamer." Let go of the day's events and allow your mind to quiet as we travel to a busy coastal town. Tonight, you’ll meet Sophia, a painter whose vibrant and expressive works reflect the world around her, yet finds her own nights restless and her mind unable to settle. Her creativity is blocked and her thoughts race, keeping peaceful sleep just out of reach.

Just as she sits by her window, watching the waves, a familiar, gentle vessel appears: The Dreamer. It has sensed her need for rest and has come to carry her away from the chaos. Join Sophia as she steps aboard, feeling the worries of the day begin to dissolve with the gentle motion of the boat. Let the vivid imagery of a secluded, moonlit cove and the soothing rhythm of lapping waves guide you toward your own state of deep calm. As Sophia finds profound peace and a restorative night’s sleep, allow this narrative to do the same for you, quieting your mind and carrying you to a place of deep, restful slumber.

Matt will be the first to tell you that launching his sleep-related merchandise sales was incredibly smooth, thanks to our new sponsor Shopify and their integrated sales and inventory system. And now, just for you,  Shopify is generously offering an exclusive trial at shopify.com/mattwalker. Whether it's online or in-person sales, Shopify simplifies it all. So, be sure to stop in at shopify.com/mattwalker to start your exclusive journey now!

As always, if you have thoughts or feedback you’d like to share, please reach out to Matt on Instagram.

Matt: Instagram @drmattwalker or on X @sleepdiplomat

YouTube https://www.youtube.com/@sleepdiplomatmattwalker9299

Matt delves into the science of "beauty sleep" this week, revealing it as somewhat of a scientific reality. He highlights research by Dr. Tina Sundelin, which demonstrates that sleep-deprived individuals are consistently perceived as less healthy, more fatigued, and less attractive. These visible changes are rooted in biological consequences like dilated under-eye blood vessels and elevated cortisol, a hormone that degrades vital skin collagen.

Matt then differentiates between expression wrinkles and a distinct second class, sleep wrinkles, which are caused by the mechanical compression of the face against a pillow. To mitigate their formation, he explains several evidence-based strategies. These include adjusting your sleep posture to your back, using silk or satin pillowcases to reduce friction, and maintaining skin hydration to improve its natural elasticity. The episode concludes with a powerful reminder that while these scientific interventions are effective, true attractiveness comes from within, encouraging a graceful embrace of the natural aging process.

Please note that Matt is not a medical doctor, and none of the content in this podcast should be considered medical advice in any way, shape, or form, nor prescriptive in any way.

One of our sponsors this week is the biochemical electrolyte drink company LMNT, and they are very kindly offering eight free sample packs when you purchase any one of their orders at drinklmnt.com/mattwalker. LMNT is an electrolyte sports drink that I can get behind - it's created from the basis of science, and it has no sugar, no coloring, and no artificial ingredients – all qualities that are so important to maintaining your blood biochemical balance. And now their new Lemonade Salt is squeezing onto the scene Tuesday, May 20th! This limited-time flavor is here to keep you at your best all summer long, and, just like summer, it’s here for a good time, not a long time, so stock up while supplies last! If you want to give Lemonade Salt or any of the fantastic LMNT flavors a try, just head on over to drinklmnt.com/mattwalker and get your free Sample Pack with your first purchase.

Tired of untrustworthy protein shakes? Show sponsor Puori prioritizes quality: hormone-free, GMO-free, and pesticide-free. Every batch is third-party tested for 200+ contaminants - you can even scan the QR code for lab results! Matt recommends the addictive dark chocolate flavor with 21g of protein. Ready to experience the Puori difference? Matt’s listeners get 20% off, so visit puori.com/mattwalker today!

As always, if you have thoughts or feedback you’d like to share, please reach out to Matt or Eti:

Matt: Instagram @drmattwalker, X @sleepdiplomat, 

YouTube https://www.youtube.com/@sleepdiplomatmattwalker9299

Dr. Eti Ben Simon returns for yet another AMA episode, this time specifically focussing on sleep and women. Together, they delve into the nuanced differences in sleep patterns between men and women, exploring aspects like sleep duration, quality, and architecture, including variations in deep sleep and REM sleep. They discuss how females generally sleep slightly longer, experience fewer awakenings, and have more deep sleep early in the night, alongside a quicker onset of REM sleep. The conversation also touches upon the potential health risks associated with shift work, particularly night shifts, highlighting an observed associational link with increased risks for certain cancers, such as breast and skin cancer, though emphasizing this is not necessarily causal.

The discussion then transitions to the profound impact of hormonal changes on female sleep throughout different life stages. Matt and Eti examine the common sleep disturbances during pregnancy, detailing the reasons such as physical discomfort, hormonal shifts, and frequent urination, and the consequences like mood disorders and increased risk of gestational diabetes. They further explore how sleep is affected by the menstrual cycle, with changes in REM and deep sleep across follicular and luteal phases, and then tackle the significant sleep challenges during menopause, including insomnia, sleep apnea, and restless legs syndrome, discussing management strategies like HRT and CBT-I.

Please note that Matt is not a medical doctor, and none of the content in this podcast should be considered medical advice in any way, shape, or form, nor prescriptive in any way.

Tired of untrustworthy protein shakes? Show sponsor Puori prioritizes quality: hormone-free, GMO-free, and pesticide-free. Every batch is third-party tested for 200+ contaminants - you can even scan the QR code for lab results! Matt recommends the addictive dark chocolate flavor with 21g of protein. Ready to experience the Puori difference? Matt’s listeners get 20% off, so visit puori.com/mattwalker today!

Having personally used and purchased AG1 for over four years, Matt encourages you to try the new AG1 Next Gen formula with upgraded probiotics plus additional vitamins and minerals. Backed by 4 human clinical trials demonstrating a boost in healthy gut bacteria, AG1 continuously adapts to the latest science. Subscribe today and receive a FREE bottle of AG D3K2, an AG1 welcome kit, and 5 upgraded AG1 travel packs with your first order. Visit drinkag1.com/mattwalker to learn more and get started on your health journey.

Matt’s good friend Dr. Peter Attia has helped develop David, a revolutionary new protein bar, and a sponsor of today’s episode! 28g of protein, 0g sugar, only 150 calories – the best ratio EVER! Amazing taste, six flavors, incredibly satiating, and a great source of the protein that helps build muscle, manage metabolic health, and keep you full. Visit davidprotein.com/mattwalker now for an amazing deal: Buy 4 cartons, and get a 5th FREE! . Hurry! Your new favorite protein bar awaits!

As always, if you have thoughts or feedback you’d like to share, please reach out to Matt or Eti:

Matt: Instagram @drmattwalker, X @sleepdiplomat, 

YouTube https://www.youtube.com/@sleepdiplomatmattwalker9299

Eti: X @etoosh, Instagram https://www.instagram.com/eti_bensimon/,  or email at [email protected]