(Updated May 2022)
Several years ago, during the depths of the New Zealand winter, our family needed to prepare for an active holiday of cycling, running, walking and swimming our way around the tiny tropical nation of Vanuatu. The big challenge was to survive the shock of going from winter to 30 degrees heat and 90% humidity, including cycling for several hours per day in tropical heat and humidity. Our solution was to spend time in a sauna. We did this once a week for about three months leading up to our departure.
Progress in our heat adaptation before departure was significant: My sauna tolerance increased from just 15 minutes to over an hour without having to go out for a cold shower.
In 1976, I contested the 2nd annual Round Rarotonga Road race, which was 19 miles around the island of Rarotonga during October when the weather can be 98% humidity and 30 Degrees Celcius heat. That was going to be very tough to go straight from the depths of a Wellington Winter to the oppressive heat and humidity of the Cook Islands! So I prepared by running in a sauna.
To my great surprise, I came 2nd behind the New Zealand Marathon Champion, Graeme Struthers, and I beat John Walker, the first person to run the mile in less than 3 minutes and 50 seconds!
The benefits of a regular sauna go well beyond preparing for a mid-winter tropical holiday.
Benefits from regular use of a sauna (Heat, profuse sweating and cold)
(When I say regular; that is about once or twice a week)
Sweating removes toxic substances safely and rapidly from the body.
It removes toxic chemicals from the body gently and safely.
It improves chronic and acute infections by heating the body one or two degrees to enhance immune system activity.
It helps remove debris and congestion in and on the skin to regenerate it.
It shunts the blood to the body surface to reduce heat. This process helps decongest the internal organs such as the liver, kidneys, spleen and pancreas for improved organ function.
It moves blood throughout the body for improved circulation and oxygenation.
It moves the lymph fluid throughout the body for improved lymphatic drainage.
It is beneficial for many conditions, including heart disease, cancer, fibromyalgia, chronic fatigue, infections, etc.
Please set aside some time to watch the following two videos:
Dr Rhonda Patrick:
"Sauna questions answered with expert Dr Rhonda Patrick: Infrared vs traditional saunas? Can sauna bathing lower the risk of dementia, heart disease, stroke, depression, and all-cause mortality? How exactly should we use saunas for optimal benefit (duration, frequency, temperature, etc.)?"
Timestamps for Dr Patrick:
00:00:00 - Intro to Saunas and Rhonda Patrick
00:01:04 - Summary of sauna health benefits (lowers dementia, cardiovascular, depression risk, etc.)
00:07:09 - A review article vs primary research and Dr. Jari Laukkanen
00:07:58 - More on cardiovascular benefits of sauna
00:10:48 - Does sauna use lower hypertension risk?
00:11:56 - Sauna use may improve fitness and endurance
00:14:48 - Can sauna use lower Alzheimers and dementia risk?
00:16:43 - What are heat shock proteins?
00:19:18 - Dr. Patrick's research on amyloid-beta 42 / heat shock proteins
00:20:30 - How Rhonda Patrick became interested in Saunas
00:22:20 - Endorphins, opiate receptors, depression, and sauna use
00:26:36 - Sauna associated with lower inflammatory markers
00:27:14 - Interleukin 6 (IL-6) and sauna use
00:29:20 - Brain-derived neurotrophic factor (BDNF) and neuroplasticity
00:32:01 - More cellular repair mechanisms (NRF2) and hormesis
00:34:00 - Eustress and intermittent fasting
00:37:38 - Sauna and muscle atrophy
00:39:54 - Excretion of heavy metals and toxins through sweat
00:41:58 - Heart rate variability and sauna use
00:43:30 - Sauna mimics moderate-intensity exercise
00:47:32 - What Rhonda Patrick does in the sauna
00:49:22 - Countries / cultures utilizing hyperthermia
00:51:34 - Infrared sauna benefits vs. traditional Finnish sauna (and waon therapy)
00:55:39 - Details about Rhonda Patrick's sauna routine (temp., duration, dry vs. humid etc.)
01:01:43 - Utilizing sauna to extend a workout
01:02:33 - Can a long hot shower or bath mimic sauna benefits?
01:03:27 - Hydration before and after sauna bathing
01:04:36 - Cold exposure after sauna use?
01:06:24 - How to tell if in the sauna for too long?
01:08:10 - Contraindications/people who shouldn't use sauna
01:12:28 - Continuous glucose monitors and sauna
01:14:25 - Limitations of current sauna research
01:18:06 - More on Finland and saunas
01:18:50 - More on heat shock proteins
01:19:46 - Closing thoughts
Dr Patrick notes:
“Compounds like heavy metals ... phthalates or BPA can be excreted through sweat or ... through urine. Some are excreted more predominantly through sweat and others are more predominantly excreted through urine, so for the ones that are more predominantly excreted through sweat, you can imagine the robust effect that sauna use has on them — cadmium being one.
There's been studies looking at sweating from sauna use where there's a 122-fold increase in sweating out cadmium. Another one is aluminium. Aluminium is also excreted quite well from sweat, and you do excrete things like BPA, [even though] the major pathway that BPA is eliminated through is through urine.”
Professor Andrew Huberman:
"Andrew describes how deliberate heat exposure impacts body temperature, metabolism, heart health, hormone production, exercise recovery, cognition, mood, and longevity. I detail specific protocols for deliberate heat exposure, including exposure times, temperature ranges to consider, time of day, and delivery mechanisms (sauna vs hot bath vs open-air heat, etc.) in order to achieve different specific outcomes, including dramatic growth hormone releases, or reduction in cortisol levels. I also discuss the ability of locally applied heat to heal or otherwise improve various bodily tissues and new data on how local application of heat may induce the conversion of metabolically sluggish white fat to metabolically robust beige fat."
Huberman's deep dive video into the sauna is below, although the number of adverts throughout the presentation is annoying. Your alternative is the podcasts on either iTunes or Spotify here: https://hubermanlab.com/the-science-and-health-benefits-of-deliberate-heat-exposure/
Timestamps for Huberman:
00:00:00 Heat & Health
00:03:37 Momentous Supplements
00:04:52 The Brain-Body Contract
00:05:46 LMNT, InsideTracker, ROKA
00:09:31 Body Shell Temperature vs. Body Core Temperature
00:13:28 Thermal Regulation, Hyperthermia
00:17:36 Heat Removal Circuits, Pre-Optic Hypothalamus (POA)
00:26:30 Protocols & Benefits of Deliberate Heat Exposure
00:33:37 Tools & Conditions for Deliberate Heat Exposure
00:38:47 Deliberate Heat Exposure, Cortisol & Cardiovascular Health
00:44:50 Heat Shock Proteins (HSPs), Molecular Mechanisms of Heat Regulation
00:47:56 Longevity & Heat Exposure, FOXO3
00:52:30 Deliberate Cold & Heat Exposure & Metabolism
00:54:48 Deliberate Heat Exposure & Growth Hormone
01:04:32 Parameters for Heat & Cold Exposure
01:08:26 Circadian Rhythm & Body Temperature, Cold & Heat Exposure
01:12:00 Heat Exposure & Growth Hormone
01:16:20 Tool: Hydration & Sauna
01:17:10 Heat, Endorphins & Dynorphins, Mood
01:28:44 Tool: Glabrous Skin To Heat or Cool
01:35:33 Local Hyperthermia, Converting White Fat to Beige Fat, Metabolism
01:47:00 Hormesis/Mitohormesis & Heat/Cold Exposure
01:49:11 Benefits of Heat Exposure
01:51:10 Zero-Cost Support, YouTube Feedback, Spotify & Apple Reviews, Sponsors, Momentous Supplements, Instagram, Twitter, Neural Network Newsletter
How to use the Sauna
Many benefits there may be, but these depend on the proper use of the Sauna. Here is the simple procedure I recommend:
If you have a medical condition, like diabetes or heart disease, please take extra care, avoiding extremes while the body acclimatises to the heat and cold cycles. Have someone accompany you at all times in the Sauna and when changing.
Begin with a warm shower, use soap to clean your body, and enter the Sauna with wet skin and hair.
Remain in the Sauna until sweating profusely with the capillaries and sweat glands dilated fully. How long this takes depends on how hot the Sauna is and how acclimatised you are.
Exit the sauna and take the coldest shower you can get out of the tap. Stay under the cold water. Cool the entire body as quickly as possible so that the capillaries and pores of the skin clamp tight.
Do not hang around: Return to the Sauna right away after the long, cold shower and remain there until again, sweating profusely.
Repeat the cold shower and Sauna cycle several times (Be conservative for the first few times while you acclimatise).
Finish with a cold shower to clamp the pores tight for the last time, and stay under the water until you feel your core body temperature is down to normal.
Drink water during and after the Sauna, and salt your food generously for several days, if not permanently. Use pink multimineral salt on your food rather than refined salt or drink a commercial electrolyte replacement. In addition to sodium, pink salt has all trace nutritional elements. If you worry that salt may elevate your blood pressure, please don't. Salt-induced hypertension is rare, and the best way to allay any fears is to measure blood pressure. Read this article: https://www.garymoller.com/post/i-ve-got-high-blood-pressure-can-you-help-me
If you weigh yourself before and after, you will know how much you need to drink to ensure you are rehydrated (1kg bodyweight loss is one litre of water to drink over the next few hours). Then, add an extra half litre of water on top of whatever was lost.
After about three weeks of regular use (once or twice a week), your heat tolerance will be much better than before, and you may notice subtle improvements to health such as better sleep, calmer nerves and smoother, healthier skin. In addition, fingers and toes may be warmer than usual despite the cold winter weather. Finally, there may now be significant improvements in blood pressure if high blood pressure was an issue.