In this episode my guest is Susanna Søberg, PhD. She earned her doctoral degree at the University of Copenhagen in Denmark, where she researched the effects of deliberate cold and heat exposure on metabolism and other aspects of human physiology. We discuss how cold exposure or sauna use can improve metabolism, cardiovascular and brain health, balance hormones and decrease inflammation. Dr Søberg explains how deliberate cold protocols can improve glucose metabolism and insulin sensitivity and trigger the release of neurotransmitters like dopamine and norepinephrine, which enhance energy, mood and focus. We compare cold showers and cold immersion, traditional and infrared saunas and other variables. This episode provides actionable tools and answers to common questions about the use of deliberate cold and heat to improve health. Thank you to our sponsors AG1 (Athletic Greens): https://athleticgreens.com/huberman Plunge: https://plunge.com/huberman Maui Nui: https://mauinuivenison.com/huberman Thesis: https://takethesis.com/huberman InsideTracker: https://insidetracker.com/huberman Momentous: https://www.livemomentous.com/huberman The Brain Body Contract Tickets: https://hubermanlab.com/tour Presale code: HUBERMAN Huberman Lab Social & Website Instagram: https://www.instagram.com/hubermanlab Twitter: https://twitter.com/hubermanlab Facebook: https://www.facebook.com/hubermanlab LinkedIn: https://www.linkedin.com/in/andrew-huberman Website: https://hubermanlab.com Newsletter: https://hubermanlab.com/neural-network Dr. Susanna Søberg Winter Swimming: The Nordic Way Towards a Healthier and Happier Life: https://amzn.to/3MsyxW0 The Soeberg Institute: https://www.soeberginstitute.com Publications: https://www.soeberginstitute.com/research Twitter: https://twitter.com/SusannaSberg1 Facebook: https://www.facebook.com/susannasoeberg YouTube: https://www.youtube.com/@resetlabpodcast TikTok: https://www.tiktok.com/@susanna_soeberg Instagram: https://www.instagram.com/susanna_soeberg Articles Altered brown fat thermoregulation and enhanced cold-induced thermogenesis in young, healthy, winter-swimming men: https://bit.ly/3MqCNWb Human physiological responses to immersion into water of different temperatures: https://bit.ly/3IumXX1 Variations in leptin and insulin levels within one swimming season in non-obese female cold water swimmers: https://bit.ly/3MpX0eF Mapping of human brown adipose tissue in lean and obese young men: https://bit.ly/3pEd6Zg A role for brown adipose tissue in diet-induced thermogenesis: https://go.nature.com/3Ob03ZI Association Between Sauna Bathing and Fatal Cardiovascular and All-Cause Mortality Events: https://bit.ly/33P09RC Impact of cold exposure on life satisfaction and physical composition of soldiers: https://bit.ly/3kMxG7G Thermal effects of whole head submersion in cold water on nonshivering humans: https://bit.ly/3I8JA4l Thermoregulation during rest and exercise in the cold in pre- and early pubescent boys and in young men: https://bit.ly/3Ia1fsg Timestamps 00:00:00 Dr. Susanna Søberg 00:03:23 Sponsors: Plunge, Maui Nui, Thesis 00:06:49 The Brain-Body Contract 00:07:40 Physiology in Uncomfortably Cold Environments 00:12:05 Tool: Water Temperature, “Cold Shock” & Discomfort 00:17:37 Cold Showers vs. Immersion in Water, Brown Fat 00:22:11 Cold Receptors, Brown Fat & Temperature Homeostasis 00:25:22 Shiver, “After Drop”, Healthy Stress 00:31:08 Long-Term Health Benefits of Deliberate Cold Exposure 00:35:48 Sponsor: AG1 (Athletic Greens) 00:37:02 Blood Pressure & Heath 00:38:26 Brown Fat, Insulin Sensitivity & Metabolism 00:45:07 Temperature Regulation, Brown Fat vs. White Fat 00:52:26 Cold Resilience, Scandinavia 00:59:07 Sponsor: InsideTracker 01:00:16 Winter Swimmers & Brown Fat; Discomfort 01:10:28 Sex differences & Brown Fat, Cold-Adapted 01:15:21 Diving Reflex & Parasympathetic Activation 01:18:44 Tool: Deliberate Cold & Sauna Protocol 01:23:11 Winter Swimmers, Shiver; Circadian Rhythm & Brown Fat 01:31:14 Tool: Minimum Threshold for Cold & Heat; Sauna & Cardiovascular Health 01:35:19 Tool: Maintaining Stimulus when Cold-Adapted; Shorter Sessions 01:38:09 Cold Exposure, Sleep Quality, Clothing 01:47:37 “Brown Fat Negative” & Shiver 01:52:13 Cold & Heat, Inflammation Reduction 01:55:40 Tool: “Soberg Principle”: End on Cold, Metabolism 01:59:39 Cold Exposure: Fed or Fasted? 02:00:32 Raynaud’s Syndrome; Hand/Feet Protection in Cold 02:05:21 Tool: Headache & Cold Exposure; Head Submersion & Head Coverings 02:11:29 Children & Hypothermia Risk 02:17:16 Gender Differences & Cold Exposure 02:19:57 Tool: Brief, Repeated Temperature Changes; Circadian Rhythm & Temperature 02:27:53 Zero-Cost Support, YouTube Feedback, Spotify & Apple Reviews, Sponsors, Momentous, Social Media, Neural Network Newsletter Title Card Photo Credit: Mike Blabac - https://www.blabacphoto.com Disclaimer: https://hubermanlab.com/disclaimer