This episode discusses metabolism and how our thyroid hormone and growth hormone control our metabolism. I also clarify that metabolism isn't just about burning energy, it’s about converting energy from different sources into fuels for building and repairing our tissues such as muscle, brain, and tendons and mobilizing energy from body fat storage. I discuss the role of iodine, selenium, and salt for thyroid health, and how specific exercise protocols, amino acids and temperature can dramatically shift levels of growth hormone release in waking and in sleep. I also describe the current landscape of prescription compounds, peptides and other factors for changing levels of thyroid and growth hormone, and some of their risks. Throughout the episode, mechanisms and tools grounded in specific mechanisms are discussed. Thank you to our sponsors Four Sigmatic: https://foursigmatic.com/huberman Blinkist: https://blinkist.com/huberman Munk Pack: https://munkpack.com - Use code: huberman Supplements from Thorne https://www.thorne.com/u/huberman Timestamps (00:00:00) Introduction (00:06:05) Thyroid & Growth Hormone (00:08:44) Food Shapes: Do They Matter? (00:11:43) Stevia: Naming & Impact (00:13:30) Metabolism 101: Your Brain the Furnace (00:17:33) Releasing Hormones From Your Brain, Stimulating Hormones from Your Pituitary (00:21:04) Thyroid Hormone’s Real Effects: Growth, Repair and Energy Consumption of Tissues (00:22:45) Iodine, L-Tyrosine & Selenium: The Trio Essential For Thyroid Function (00:26:05) How Much Iodine Do We Need? By Food, Supplement or Ocean Air (00:28:09) Selenium For Thyroid: Brazil Nuts & Other Valuable Sources (00:33:05) Selenium For Pregnancy, Prostate Cancer Risk, Acne (00:35:20) “Clean Eating” Downsides: Cruciferous Vegetables, Leeching Iodine (00:39:00) Other Benefits of Iodine: Reducing Inflammation (00:41:00) Why & How Increased Thyroid Increases Metabolism (00:42:12) What To Eat To Support Your Brain (00:43:00) Hyperthyroidism (Too Much) & Hypothyroidism (Too Little) (00:44:35) Menstruation: Thyroid Carbohydrate & Sugar Craving (00:45:33) Ketogenic Diet & Its Effects On Thyroid, Rebound Weight Gain (00:48:39) Growth Hormone: What, Why & How (00:51:18) Growth Hormone (GH) Changes Across The Lifespan & Risks of GH Therapy (00:53:40) How To Powerfully Increase Growth Hormone: Know The Natural Triggers (00:54:49) Not Eating Within 2hrs of Sleep: Keep Blood Glucose Low(ish) At Sleep (00:55:43) Delta Wave Brain Activity Is the Trigger For Growth Hormone Release (00:58:25) LOW Doses of Melatonin Supplementation For Increasing GH Release (01:01:00) Book: Altered Traits, Binaural Beats? Delta Waves Access (01:04:35) Specific Types & Duration of Exercise That Stimulate Growth Hormone & Warmups (01:08:40) Keeping Low Blood Glucose & Ensuring A Cool Down For Two Phase GH Release (01:10:36) Sex Differences For WHEN During Exercise Growth Hormone and IGF-1 Release Occurs: Males Have To Last Longer (01:14:10) Supplements That Increase Growth Hormone 100-400% (or more): Arginine, Ornithine (01:18:20) Arginine & Exercise Together Can Be Counter-Productive (01:19:50) L-Citrulline Better For Arginine Than Arginine Itself (?!); & Blood Pressure Caution (01:23:09) Growth Hormone Changes Across The Lifespan: No One Escapes (01:26:00) Heat (& Cold) for Triggering Extremely Large Increases In Growth Hormone (01:29:20) Specific Heat Protocols For Increasing Growth Hormone: Up To 16-Fold (?!) (01:34:30) 2021 (New) Study: Heat Increases GH, & Lowers Cortisol, No Effects On Testosterone, DHEA Or Prolactin (01:36:00) Prescription Growth Hormone, & Emerging Peptides Therapeutics, Secretagogues Etc. (01:42:25) Synthesis, Summary Of Actionable Steps For Increasing GH and Thyroid Hormone (01:44:00) Zero Cost & Other Ways to Support Our Podcast; & Thank You!