Matt explores a revolutionary shift in sleep science, identifying the gut microbiome as a secondary control center for rest. He elucidates the bidirectional gut-brain axis, where the Vagus nerve connects trillions of microorganisms to the brainstem, and details how bacterial metabolites, specifically the short-chain fatty acid butyrate, trigger critical BDNF-TrkB signaling to orchestrate deep NREM sleep. Using Parkinson’s disease as a model, he demonstrates how gut dysbiosis undermines sleep architecture and ramps up neuroinflammation, proving our intestinal health is inextricably linked to nightly stability. Matt discusses how dietary choices and circadian regularity influence this microbial ecosystem, highlighting prebiotic fibers like beta-glucan, which provide the essential fuel for bacteria to produce sleep-promoting compounds. He also reviews probiotics' ability to modulate neurochemistry - reducing cortisol and increasing GABA - to facilitate a seamless transition into sleep. Ultimately, Matt argues that sleep is a collaborative effort between neurons and microbes, suggesting that precision interventions tailored to our microbial signatures are the future of optimal 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. Podcast partner, 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! Another sponsor this week, 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 flavor while it lasts! In a supplement industry where trust is critical, Matt uses podcast supporter 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/@sleepdiplomatmattwalker9299