Can Regular Sauna Use Make You Happier and Live Longer?

Written by Andy Mobbs
featured image for article on using sauna after workout

For most people who regularly use the sauna after a workout, you don’t need to tell them it’s healthy, they can feel it! Even though it can be uncomfortable in the sauna itself, it leaves you feeling great afterwards, as long as you remember to rehydrate!

However, it’s not just a feeling, there is actually a lot of science behind why a sauna is great for physical and mental health. In this article, we’re going to go over them in detail, which should hopefully give sauna fans extra motivation to keep getting a sweat on as often as possible. And perhaps, we may even get some of those who aren’t regular sauna goers to give it a go.

Sauna Discomfort is Healing

Perhaps you’re familiar with the term endorphin? It’s the feel-good chemical that our bodies release after a workout. It creates the feel-good post-workout feeling of calm and relaxation by acting on the opioid receptors in the body.

However, during the workout itself, another chemical is produced which is effectively the opposite of endorphin, and is known as dynorphin. Dynorphin is the opposite of endorphin because it creates feelings of discomfort when we exercise. As well as through exercise, another way to stimulate dynorphin is with heat stress, meaning we can significantly increase dynorphin release by using saunas.

sauna after workout can produce dynorphin
Image adapted from (1).

Dynorphin as shown in the image above stimulates the Kappa opioid receptors, which produce feelings of discomfort or dysphoria. Basically, they create an urge to get out of the sauna.

dynorphin is a good stressor and makes and amplifies the effects of endorphins
Image adapted from (1).

However, the release of dynorphin is actually a good stressor, also known as ‘eustress’, which is the scientific name for a good or beneficial stressor. A good stressor is one where the stress causes the body to positively adapt to that stress physiologically, improving health.

In the case of dynorphin, it actually leads to the production of more opioid receptors that endorphins can bind to (known as Mu opioid receptors). Also, those new Mu opioid receptors and the existing Mu opioid receptors become more sensitive to circulating endorphins.

Sauna discomfort boosts mental and physical health

This means that after regular sauna use, people develop the ability to get greater positive effects from endorphins. Endorphins help to reduce pain, stress, anxiety and depression, and this is one of the reasons why saunas are great for mental health.

Research has also suggested that saunas may help to increase serotonin levels in the brain, and serotonin is the feel-good neurotransmitter that most anti-depressant treatments try to increase (2).

These benefits have been reflected in studies that have found regular sauna use can reduce the pain associated with osteoarthritis, rheumatoid arthritis, and fibromyalgia (3, 4). Also, a Japanese study found that regular sauna use reduced the symptoms associated with mild depression (5).

Heat Shock Proteins

Sauna also significantly upregulates the production of heat shock proteins. These proteins work a little like bodyguards, by protecting other proteins from stress which can cause a change in their structure, as well as ensuring that proteins maintain their correct structure as they are made.

Heat shock proteins were originally discovered in studies where cells were exposed to heat as a stressor. But it’s now known they’re also produced in response to other stressors such as cold and injury, but heat remains a very strong stimulator of their production.

Proteins can be extremely complicated molecules, and during production, they form very intricate shapes, which allows each different protein to be used for a very specific purpose. The production process involves joining together large amounts of individual amino acids which are then extensively folded to create the very complex shapes.

sauna after workout promotes the production of heat shock proteins

If proteins lose their shape even slightly they can become useless for their intended purpose, but heat shock proteins make sure that the proteins are folded correctly, and can fold them back into place when they become misfolded.

In cells where there is stress, but not enough heat shock proteins, the number of misshapen proteins can build up. When this happens, the misfolded proteins can aggregate together with other misfolded proteins and build up in cells, and cause the whole cell to become dysfunctional. Examples of diseases where there is an aggregation of misfolded or toxic proteins include Alzheimer’s where there is a big buildup of amyloid-beta proteins known as amyloid plaques.

The 20-year Finnish sauna study…

A study conducted by Laukkanen et al at the University of Eastern Finland followed 2315 middle-aged Finnish men who either used a sauna once a week, 2-3 times per week or 4 -7 times a week for 20 years (this was a huge study and I’ll come back to it several times). The researchers found that those subjects who sauna’d 4-7 times per week were 66% less likely to suffer from Dementia and 65% less likely to suffer from Alzheimer’s than those men that had just 1 sauna a week (6).

The study was also very careful to account for any other differences between the men, such as smoking, diabetes, obesity or other exercise/lifestyle factors, to focus on just the effects of sauna.

Heat shock proteins are also suggested to cause an increase in longevity as well. For example, studies on Drosophila fruit flies and worms found that heat exposure caused a 15% increase in the life span of the flies and a 45% increase in the lifespan of the worms compared to controls. This was found to be related to an up-regulation of a specific heat shock protein known as Hsp70 (7, 8).

Increased expression of Hsp70 has also been associated with an extended lifespan in humans, whilst physical and mental decline with ageing has been shown to be related to reduced production of Hsp70 (9).

Firing Up Your Longevity Genes

Sauna also stimulates the expression of genes that are associated with increased lifespan. FOXO3 and the Sirtuin family of genes are genes that are involved in many functions in the human body that help us to live longer (12-13). They include:

  • increased energy production and the production and repair of new mitochondria
  • repairing DNA
  • reducing oxidative stress and increasing antioxidant production
  • making damaged cells commit apoptosis (cellular suicide) so they don’t become cancerous
  • increasing autophagy (cellular repair)
  • stem cell maintenance and production
  • killing senescent cells (cells which no longer function properly but continue to produce inflammatory messengers known as cytokines)

The Sirtuin genes especially became well known after playing a major part in David Sinclair’s best-selling book ‘Lifespan’, where he describes his theory on the cause of ageing and how to prevent it. Heat stress specifically has been shown to up-regulate both FOXO3 and the Sirtuin family of genes, and so sauna after workout could potentially help us to live longer (12-13).

Nitric oxide – The Master Molecule of Cardiovascular Health!

Nitric oxide is a wonder molecule for your arteries and veins. According to best-selling author and UK Doctor Malcolm Kendrick, it’s the “single most important factor for cardiovascular health there is” (15). It helps the blood vessels to relax, lowering blood pressure and stopping them from becoming stiff.

Arterial stiffness is a major risk factor for strokes and heart attacks. It’s also a powerful anticoagulant and promotes the production of endothelial progenitor cells that help to repair blood vessels.

nitric oxide is beneficial to cardiovascular health

The great news is that sauna use significantly increases the production of nitric oxide (16). Studies have also shown that sauna can reduce blood pressure in subjects that have at least one recognized risk factor for a stroke or heart attack, and sauna also reduced arterial stiffness and improved pulse wave velocity in those subjects (17-18).

And you know what else increases nitric oxide production? Omega-3 fatty acids. Docosahexaenoic acid (DHA) is an omega-3 fatty acid that helps increase nitric oxide production, causing the endothelium of the arteries to widen for increased blood flow (31).

Back to the 20-year Finnish sauna study…

The Finnish study that I mentioned earlier by Laukkanen et al found that the (healthy) men they studied who took between 4 and 7 saunas per week were 47% less likely to develop high blood pressure than those who had 1 sauna a week (19).

They also showed that those who had the most saunas per week (4-7) were over 50% less likely to die of sudden cardiac death than those who only had one sauna a week, and those that spent over 19 minutes in the sauna on each visit were 60% less likely to die of sudden cardiac death than those that spent under 11 minutes in the sauna (20).

hazard ratio for sudden cardiac death

At the same time, fatal coronary disease was 48% less likely and fatal CV disease was 50% less likely in those who had 4-7 saunas a week compared to those who only had one sauna a week (20). 4- 7 saunas a week were also associated with a reduced risk of respiratory diseases which were counted as COPD (chronic obstructive pulmonary disease), asthma, or pneumonia, and this led overall to a reduced chance of death by any cause of 40% in the group that had 4-7 saunas a week compared to 1 sauna a week.

table on hazard ratios of various cardiac diseases

Detoxification

Sauna – and specifically the sweating that it produces – helps us to get rid of environmental toxins that everyone is exposed to in our modern world. The concept of detox itself still seems to be quite controversial amongst health experts, with some believing that it’s nonsense or at best pseudoscience, however, there is much evidence to show pollution is a major health issue.

For example, our world is much more toxic than even a few years ago. Commercial chemical production has risen from 1 million tons in 1930 to 400 million tons in 2001 (21). In 2011 the WHO estimated that 4.9 million deaths per year and 86 million disability-adjusted life years are attributed to environmental chemicals (22).

A Canadian report on toxic substances found in umbilical cord blood of newborns found 137 different chemicals including dioxins, PFC’s, organochlorine pesticides, lead, mercury and PCB’s (23). In Latin America, “toxic chemicals in the environment have become an important problem and are recognized as major causes of disease and disability among children” (24). So the recognition and understanding of environmental toxins as a cause of health issues is changing, it’s just happening slowly.

The 4 Detoxification Pathways

We know the body has a very specific process for detoxifying chemicals that have been clearly defined in the scientific literature for decades. The process involves 4 phases or detoxification pathways, Phase 0, Phase I, Phase II, and Phase III. The phases take place primarily in the liver, although they also take place in the kidney, lung, intestines, skin, and testes.

The First 3 Phases

Phase 0 involves transportation proteins that take toxins into cells, and Phase 1 is a group of enzymes known as the cytochrome P450 system that oxidizes these toxins. Phase 2 then involves conjugation (joining) of the oxidised chemicals to 1 of 6 different compounds (either an amino acid, sulphur, a methyl group, glucoronic acid, an acetyl group or glutathione).

detoxification pathways

The Last Phase

In Phase 2, the conjugation process makes the toxins water-soluble. When a toxin is water-soluble, it can then be much more easily excreted from the body, either in the urine via the kidney, through the bile in feces, or in sweat (this is Phase 3).

However, one of the issues with this is that bile isn’t an efficient pathway for chemical excretion. Bile is actually reabsorbed from the gut and recirculated through the liver between 14 and 17 times, so toxins can potentially be continually recycled throughout the body (25). This wasn’t necessarily a problem throughout our evolution, as we weren’t exposed to the same level of toxins as we are now, however, now the potential toxic burden is much greater.

This is where we can utilize the sauna to significantly increase sweating to help get rid of the toxins. Although research into the sauna and reducing our toxic burden is still relatively new, we’ve had some excellent studies showing that regular sauna use can reduce levels of PCB’s, PBB’s, PBDE’s, organochlorine pesticides, and heavy metals including arsenic, cadmium, lead, mercury and nickel (26-30).

So, How Often Should I Sauna?

This really depends on your lifestyle. Life is about balance, and you need to be able to make sauna a part of your routine without it causing pressure on other life commitments. Having said that, the Laukkanen et al study did show that more saunas are more beneficial, so the more saunas you can fit into your schedule the better (this includes using the sauna after a workout session).

They also found more benefits for people who were able to sauna for 19 minutes or more per session. However, again this is dependent on the individual, as sauna is a stress, so don’t do more than you can handle. You should start with a much shorter time, and if you feel dizzy or have any other problems please leave that sauna. You’ll find your tolerance level will increase with regular use and you can slowly build up to longer sessions.

Also please remember to rehydrate after your sauna by drinking plenty of water, as it’s really important not to get dehydrated!

References

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