This week, Matt dismantles the myth that REM sleep only benefits the mind by revealing its profound importance for physical health. While deep sleep handles some repair, Matt details how REM is crucial for peak testosterone and growth hormone release, vital for muscle, bone, libido, tissue repair, and metabolism. He explains that REM's characteristic muscle paralysis (atonia) isn't just for safety; it fosters physical recovery by enabling deep muscle relaxation, boosting blood flow, lowering cortisol, and regulating inflammatory cytokines.

Matt further explores how REM resets the body's thermostat, enhances cardiovascular health through heart rate variability, and improves lung function via unique breathing patterns. This vital stage also supports genital tissue health, significantly ramps up protein synthesis for muscle repair, and strengthens the immune system by promoting essential cells and cytokines. Matt concludes that protecting REM sleep is non-negotiable, as it serves as a cornerstone for both mental and essential physical restoration and function.

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!

Another 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. If you want to give LMNT a try, just head on over to drinklmnt.com/mattwalker and get your eight free samples 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 on Instagram.

Matt: Instagram @drmattwalker or on X @sleepdiplomat

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

In this latest AMA episode, Matt and Dr. Eti Ben Simon tackle even more listener questions regarding any and all aspects of sleep. Today, they discuss sleep tracker accuracy, noting that while nightly data isn't perfect (~75-85% accurate), weekly trends are reliable. Feeling exhausted despite good tracker metrics? Potential causes include fragmented sleep, circadian issues, undiagnosed disorders (like apnea), or tracker-induced anxiety (orthosomnia). Matt and Eti stress consulting a specialist for persistent fatigue and focusing on long-term data patterns.

They also explore why many wake around 3:30 AM, linking it to shifts into lighter sleep stages and hormonal changes (cortisol rise, melatonin drop). The hosts explain alpha wave intrusion's link to nonrestorative sleep, theories behind teeth-falling-out dreams (trigeminal nerve activity), and differing sleep onset times (partner variations, potential sleep debt). They also touch upon how antidepressants affect dream recall via REM sleep reduction and debunk precognitive dreams, attributing them to statistics and cognitive bias, not prophecy.

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!

Another great sponsor of the show is AG1, a comprehensive nutritional drink trusted by thousands worldwide, including Matt! For nearly four years and counting, he has relied on AG1 to fuel his post-workout routine with its powerhouse blend of over 75 essential minerals, vitamins, probiotics, and prebiotics, meticulously crafted to support your daily nutritional needs. AG1 is registered and approved by the Therapeutic Goods Administration, boasting GMP badges for quality assurance. As a special offer for our listeners, when you try AG1, you'll receive a complimentary one-year supply of both Vitamin D and K2, and with your first subscription, you'll also receive five free AG1 travel packs! Visit AG1 to explore AG1's range of offerings and claim your exclusive offer.

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 etoosh@gmail.com

Dr. Cheri Mah returns to the podcast today to explore a few different topics including how circadian rhythms shape athletic performance. She notes that these 24-hour cycles regulate sleep, hormones, and core temperature, with peak physical capacity often occurring between 4-8 pm—when many world records are set.

Dr. Mah also discusses chronotypes, showing how tailoring training to one’s natural rhythm can enhance results. She reveals research on circadian disruption in sports, notably how West Coast NFL teams outperform East Coast teams in night games due to a three-hour body clock advantage. The episode also covers jet lag strategies, sleep loading, and managing fatigue, making it a must-listen not just for athletes and high performers, but truly for us all.

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 is only too happy to share the fact that launching his sleep-related merchandise sales was incredibly smooth, thanks to show 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!

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. If you want to give LMNT a try, just head on over to drinklmnt.com/mattwalker and get your eight free samples with your first purchase.

Another great sponsor of the show is AG1, a comprehensive nutritional drink trusted by thousands worldwide, including Matt! For nearly four years and counting, he has relied on AG1 to fuel his post-workout routine with its powerhouse blend of over 75 essential minerals, vitamins, probiotics, and prebiotics, meticulously crafted to support your daily nutritional needs. AG1 is registered and approved by the Therapeutic Goods Administration, boasting GMP badges for quality assurance. As a special offer for our listeners, when you try AG1, you'll receive a complimentary one-year supply of both Vitamin D and K2, and with your first subscription, you'll also receive five free AG1 travel packs! Visit AG1 to explore AG1's range of offerings and claim your exclusive offer.

Matt: Instagram @drmattwalker or on X @sleepdiplomat

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

Connect with Dr. Mah: https://www.drcherimah.com/ or https://linktr.ee/drcherimah

Caffeine Nap Episode: https://podcasts.apple.com/us/podcast/58-caffeine-nap/id1578319619?i=1000630666364

Chronotype Assessment: AutoMEQ: Automated Morningness-Eveningness Questionnaire (AutoMEQ)

Find tranquility in a secret setting as Matt guides you through tonight's sleep story set in "The Twilight Garden." Meet Clara, the lamp keeper, who lovingly tends to the hundreds of lanterns that illuminate this hidden haven. On this particular evening, a grieving visitor arrives, seeking solace and a way to remember a lost loved one. As Clara shares the garden's quiet magic and the healing power of light, you'll be enveloped in the garden's peaceful atmosphere, filled with the scent of lavender and the soft glow of lanterns.

Let your imagination stroll along the meandering paths as the warm light creates a sense of safety and calm. Focus on the soft rustling of leaves and the gentle cadence of Matt's voice, allowing the narrative to quiet your mind and soothe your body. Allow The Twilight Garden to lead you into a peaceful night's sleep, filled with the hope of rediscovering inner light and the comfort of shared stories.

Special thanks to our sponsor, Shopify, for supporting tonight's Sleep Story! 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: Instagram @drmattwalker, X @sleepdiplomat,

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

In today’s episode, Matt challenges the notion that REM sleep is solely for the brain, revealing its broad impact on physical health. He delves into REM's role in regulating testosterone and growth hormone, crucial for muscle function. Our host also highlights how REM aids muscle recovery via paralysis, boosting blood flow and supporting protein synthesis.

Beyond muscles, Matt explores REM's effects on temperature regulation and heart health by boosting heart rate variability and promoting stress resilience. He also uncovers REM's surprising links to reproductive and immune health, from genital blood flow to enhanced immune cell production. Matt emphasizes that prioritizing REM sleep is vital for whole-body well-being, and that, by embracing the full spectrum of REM's benefits, we can all unlock a potent pathway to not just a rested mind, but a thriving, resilient body.

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. If you want to give LMNT a try, just head on over to drinklmnt.com/mattwalker and get your eight free samples with your first purchase.

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!

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 on Instagram.

Matt: Instagram @drmattwalker or on X @sleepdiplomat

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

Matt and Dr. Eti Ben Simon team up to answer more audience questions today, and begin by delving into the subjective experience of time during dreams, exploring how our perception stretches and compresses during REM sleep and whether we can hack our dreams. They also explain the cognitive, emotional, hormonal, and immunological consequences of pulling an all-nighter, highlighting the dramatic impact on memory consolidation, stress hormones, appetite regulation, and immune function. The cardiovascular and metabolic repercussions are also addressed underscoring the serious health risks associated with chronic sleep deprivation.

The discussion shifts to the societal bias favoring morning types, challenging the notion that evening types are simply lazy. Our hosts examine chronotypes, the “sentinel hypothesis”, and the importance of aligning sleep schedules with individual preferences for optimal health. Matt and Eti then draw the episode to a close by addressing the common phenomenon of night sweats, differentiating between pathological causes and the normal thermoregulatory disconnect during REM 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.

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!

Another great sponsor of the show is AG1, a comprehensive nutritional drink trusted by thousands worldwide, including Matt! For nearly four years and counting, he has relied on AG1 to fuel his post-workout routine with its powerhouse blend of over 75 essential minerals, vitamins, probiotics, and prebiotics, meticulously crafted to support your daily nutritional needs. AG1 is registered and approved by the Therapeutic Goods Administration, boasting GMP badges for quality assurance. As a special offer for our listeners, when you try AG1, you'll receive a complimentary one-year supply of both Vitamin D and K2, and with your first subscription, you'll also receive five free AG1 travel packs! Visit AG1 to explore AG1's range of offerings and claim your exclusive offer.

As a health fanatic, Matt’s kryptonite has always been bread. Then he discovered Hero Bread: zero net carbs, zero sugar, and packed with fiber! For years, he’s enjoyed their fluffy loaves (his favorite topped with tomatoes, balsamic, and parmesan). Now, you can try it too! Hero Bread offers a delicious variety of healthy bread options, from tortillas and wraps to bagels and dinner rolls. Ready to enjoy bread again? Get 10% off your order at hero.co using code MATTWALKER.

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 etoosh@gmail.com

Matt Walker welcomes Dr. Ranji Varghese back to the podcast today to complete the whole sleeping pill story by discussing newer sleeping pills, beyond benzos and Z-drugs. Together, they explore Melatonin receptor agonists (like Ramelteon) that signal sleep preparation, unlike sedating GABAergics. They also detail how DORAs inhibit the wakefulness-promoting orexin, how off-label options (ex. trazodone, low-dose doxepin) affect histamine, the risks and benefits of each.

Dr. Varghese goes on to explain the mechanisms and side effect profile for each sleeping pill, including over the counter options. He stresses that all medications carry risk and require careful use, noting that sleeping pills are tools not cures, and that CBTI is preferred for chronic insomnia. Our duo finish up by reminding listeners that open communication with your doctor is vital for safe, short-term medication use.

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. If you want to give LMNT a try, just head on over to drinklmnt.com/mattwalker and get your eight free samples 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. Varghese:

LinkedIn: https://www.linkedin.com/in/ranji-varghese-md-3591665a/

Minnesota Regional Sleep Disorders Center:
https://www.hennepinhealthcare.org/specialty/minnesota-regional-sleep-disorders-center/

Institute for Integrative Therapies: @iit-mn.com

Instagram: https://www.instagram.com/docvarghese/?hl=en

X: https://x.c

Escape into a world of untold stories with Matt as he guides you through tonight's sleep story set in "The Archive of Lost Letters." Meet Stephanie, the archivist, who tends to letters never sent, filled with unspoken confessions and unshared truths. Tonight, a visitor arrives, searching for a lost piece of himself. As Stephanie helps him uncover a forgotten letter, you'll be enveloped in the library's quiet atmosphere, filled with the scent of old parchment and the weight of unspoken words.

Let your imagination wander through the endless shelves of envelopes as the soft amber glow of the lamps create a sense of calm. Focus on the gentle rustling of paper and the soft cadence of Matt's voice, allowing the narrative to quiet your mind and soothe your body. Allow the Archive to guide you into a peaceful night's sleep, filled with the possibility of rediscovered feelings and the comfort of letting go.

Special thanks to our sponsor, Puori, for supporting tonight's Sleep Story! Matt is a huge fan of this superb company and their guaranteed hormone-free, GMO-free, and pesticide-free supplements so be sure to check them out.

To save 20%, go to puori.com/mattwalker and use the code ‘mattwalker’ at checkout.

Matt: Instagram @drmattwalker, X @sleepdiplomat,

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