"We did not just discover how to end a session. We discovered how to design one. Thermalist® is my commitment to making sure that science translates into real-world practice — so that every person and every facility using contrast therapy is working toward genuine, long-term health outcomes. Not just exposure. Results."
Dr. Susanna Søberg is a PhD scientist in metabolism, international bestselling author, and the founder of the Søberg Principle and Thermalist® — the world's leading science-based contrast therapy system.
Over 15 years of peer-reviewed research at the University of Copenhagen led to a landmark 2021 publication in Cell Reports Medicine — establishing the Søberg Principle, now adopted by millions worldwide and applied in wellness settings across more than 25 countries.
Her work has been discussed by Andrew Huberman and Joe Rogan on The Joe Rogan Experience, featured in The New York Times, The Times, The Guardian, and BBC Radio, and embraced by some of the world's highest-performing athletes and business leaders.
She is a sought-after keynote speaker — most recently at Global Wellness Summit, Eudemonia, FIBO, one of the world's largest wellness and fitness trade events, and at Future Tense, speaking to business leaders on performance and nervous system regulation. She speaks on contrast therapy, metabolic health, stress physiology, longevity, and the science of human performance.
Beyond research and speaking, Dr. Søberg translates her science into four online courses at the Søberg Institute — taken by thousands of students across 127 countries — and the Thermalist® Recovery System, a licensed contrast therapy operating system for premium wellness facilities and hospitality operators worldwide.
Her mission has never changed: to make world-class science accessible to the people who need it most — and to build the infrastructure that brings it into the real world at scale.
Latest Publications
CELL REPORTS MEDICINE
Peer-reviewed research published in Cell Reports Medicine in 2021 confirming that structured contrast therapy — the deliberate alternation of cold and heat exposure — produces measurable metabolic outcomes including brown fat activation and improved insulin sensitivity. The scientific foundation of the Søberg Principle and the Thermalist® Method.
CELL METABOLISM
Delve into the intricate biology behind our preferences for palatable foods, particularly sweets, and the role of the hepatokine fibroblast growth factor 21 (FGF21) in regulating sugar consumption, shedding light on the complex interplay between genetics and eating behaviors.
As featured in
Bring the Thermalist® Recovery System to Your Facility
The Thermalist® Recovery System is a complete, science-based contrast therapy operating system — built on the peer-reviewed Søberg Principle and 15 years of research. Structured programmes, staff certification, guided experiences, and a member ecosystem designed to drive retention, revenue, and real measurable health outcomes.
The work you are doing is very important. As an interventional pain management physician I am always looking for non invasive ways for patients to improve their health and pain.
Dr. Søberg you have helped me so much with my new cold water plunge routine. I look forward to learning more about the optimum time to increase my metabolism, eliminating weak mitochondria and more. Thank you!
Thank you from Australia! I am excited to learn more and love the work you are doing. I have started cold plunging for the past 10 weeks and noticing benefits but also dealing with problems such as reynauds and chilblains. I hope I can learn more to help me on my journey
Thank you for making the science of beath, cold and heat so accessible. Looking forward to becoming your first instructor from South Africa.
My husband and I love your work. We've done Bikram since 2008 and now I'm teaching it. Your work in cold is of great interest and you've inspired us to put in a cold plunge. Thank you!
I am fascinated by your knowledge of metabolism and all things hot and cold. I am on my own wellness journey that includes nutrition, cold plunge and infrared heat.
I find your work really interesting. It supports my work as a cold water therapy coach, breathing coach and menopause wellbeing practitioner. I'm interested in your Thermalist Instructor Course as well, so want to keep up to date with your work. Thank you
Thank you for providing us with more science and information. I really hope to in the future join your courses and become a thermalist myself.
The principles that you endorse have proven very effective for our family's health and physical performance
I first learned of you from Peter Attila's Podcast. I was so intrigued by your work. Thank you!
Thank you so much for all of this incredible information you put on. From the first time that I erased myself in an ice bath I went in to total shock and had no idea about the physiological effects that were occuring. After reading your first book and listening to many of your podcasts I now use this information to help men tackle mental health issues in my Men's group events.
Love your story, heard you on many different podcasts and you got me talking cold showers and talking about it to many of my patients. Keep up the great work!
I love how you really care about people's health
Glad to support your work as it has already made mine and my families life better!
I run a sauna and cold plunge business in New Zealand and love your work. Thank you for sharing this knowledge in a digestible way.
I'm sincerely hoping your information on the thermal therapy will help my wellness journey post pulmonary embolism
I'm excited to learn more about the cold water immersion and breath work. Looking forward to learning more about the instructor program.
You have changed my life and I'm hoping I can change others using your information. Thank you
Thank you for sharing such vital data in actionable ways!
I love your thoroughly evidenced approach while communicating effectively without scientific jargon. Thank you
