Story at-a-glance

• Research shows sauna use just once a week has a positive impact on cardiovascular disease (CVD) and the incidence of fatal heart attacks; researchers also found frequency could predict long-term risk for CVD mortality
• Exposure to heat stress optimizes heat shock proteins (HSP) necessary to support mitochondrial biogenesis and helps eliminate waste products from damaged HSP, an accumulation of which may lead to plaque formation in your vascular system
• Sauna use helps detoxify your body of heavy metal buildup from environmental pollution; heavy metals such as cadmium, lead and arsenic are associated with an increased risk of heart disease
• While sauna use reduces your risk of multiple conditions and helps detoxify your body, it is wise to do heavy metal testing to assess your risk; use your sauna safely by watching your fluid and electrolyte balance, acclimating to the heat slowly and using the sauna with a buddy

Some of the simplest strategies have a tremendous impact on your health. Many produce increasing benefit, in much the same way compound interest works. In other words, little changes each day can build to produce significant impact over time. Sauna use is one of those strategies.

Historically, saunas have been an approach used in Eastern Europe, Asia and Finland for detoxification, relaxation and health.1 Athletes use extreme heat for post-workout stress reduction and to improve conditioning and athletic performance by increasing endurance.2

Exposure to extreme temperatures is also beneficial for mitochondrial functioning, the tiny powerhouses in your cells providing your body with energy required to function. Saunas provide heat stress to your body, an important way of optimizing heat shock proteins (HSP) inside the cells, triggering mitochondrial biogenesis.3

This supports your overall health, and especially your cardiovascular and brain health. Over time, HSP are damaged. An accumulation of HSP may lead to plaque formation in your vascular system. An estimated 610,000 people die from heart disease in the U.S. every year.4 Heat stress helps prevent this chain of events.5

Not surprisingly, much of the research on sauna use has come from Finland, where most people use the sauna at least once a week. Recent research6 has once again associated sauna use with a reduced risk of cardiovascular disease (CVD) mortality. This same study also finds sauna use may predict cardiovascular risk in men and women.

Sauna Use Inversely and Strongly Associated With Fatal Heart Attack

Previous evidence indicates sauna use has a positive effect on reducing the risk of fatal heart attacks and all-cause mortality in men.7 The aim of this study was to look at the relationship between sauna habits and CVD mortality in men and women.

The researchers were particularly interested in whether information on these habits could predict mortality risk. The researchers gathered data from over 1,650 participants with a mean age of 63, of whom 51.4 percent were women.

During the study period of 15 years, 181 fatal CVD events occurred, with the risk of mortality decreasing linearly with increasing sauna sessions each week. Interestingly, the researchers found no threshold effect. In other words, even one sauna session a week conferred benefits to the user.8

After adjusting for known CVD risk factors and potential confounding factors, the researchers found the duration of use was inversely associated with mortality. They also found the additional information on frequency provided predictive value of the long-term risk for CVD mortality.

The authors offered several explanations for this reduction in risk, including an increased demand on the cardiovascular system without active muscle work, and the fact that heat exposure has blood pressure-lowering effects, decreasing peripheral vascular resistance and arterial stiffness.9

This supports previous data from the University of Eastern Finland where researchers tracked 2,300 middle-aged men for an average of 20 years. Over the course of the study, 49 percent of the men who used the sauna once a week died as compared to 38 percent who used it two to three times a week and just 31 percent of those who used it four to seven times per week.10

Heat Stress Improves Fitness Affecting Heart Health

Saunas increase nitric oxide (NO) production in much the same way as high-intensity exercise. NO is a potent vasodilator that stimulates your brain, kills bacteria, defends against tumor growth and helps boost muscle growth and strength.11

Another benefit to fitness can be attributed to thermogenesis. Exposure to extreme temperatures improves mitochondrial function. When your mitochondria are not working properly, your body's ability to generate energy is impaired. The key is to eliminate old mitochondria and generate new ones — a process called biogenesis.

Strategies to support mitochondrial biogenesis are exposure to extreme hot or cold temperatures, exercise and intermittent fasting. Each of these stimulates a transcription coactivator, which is the primary driver for mitochondrial biogenesis. Cardiovascular functioning and good health are dependent on a strong system of functioning mitochondria.

Sauna Use Helps Rid Your Body of Heavy Metals

Yet another benefit to sauna use is helping to boost the elimination of toxins, including pesticides and heavy metals such as cadmium, arsenic, lead and mercury. Even if you may live a relatively clean lifestyle, it is not uncommon to acquire heavy metals from cosmetics or secondhand smoke or vaping.

Near-infrared saunas are particularly beneficial for detoxifying heavy metals as they heat your tissue several inches deep and enhance your natural metabolic processes, blood circulation and tissue oxygenation.

A problem with reduced sweating may be the result of an increased toxic load, which in turn can adversely affect your heart and brain health. Compared to other strategies to detoxify from heavy metals, sauna use may be one of the best, as it lowers your toxic load in a natural way.

As discussed in a previous interview with Dr. George Yu, mobilizing stored toxins for removal may be enhanced by using niacin (vitamin B3). Niacin helps mobilize fat, freeing up toxic chemicals in lipophilic tissues such as your brain. When taken in conjunction with sauna use, the mobilized toxins are safely eliminated through your sweat.

Heavy Metal Poison Increases Your Risk of Cardiovascular Disease

Acute heavy metal poisoning, such as what happens when you receive a high dose at one time, leaves you feeling confused, vomiting, passed out or numb. However, it's more likely you will have a buildup of heavy metals in your system over time, resulting in symptoms such as headache, weakness and tiredness, achy joints and muscles, or constipation.12

Another effect of long-term exposure to heavy metals is CVD. Traditionally, heavy metal toxicity is not counted as a risk factor for CVD.13 However, you likely have been exposed through food, water and your environment. Once in your body, metals displace essential minerals such as calcium and magnesium and increase the rate of inflammation.

Repeatedly, large studies like the National Health and Nutrition Examination Survey have found heavy metal levels are correlated with cardiovascular health.14 Other perspective studies have confirmed the presence of cadmium,15 lead16 and arsenic17 are associated with hypertension, peripheral vascular disease and other CVD risks.

It is important to know adverse events don't occur only at high levels, but have also been linked to exposure below current safe standards.18 One of the unexpected positive results in a trial to assess chelation therapy was a reduction in cardiovascular events.19

The National Institutes of Health initiated a secondary study in an attempt to replicate the findings and establish the removal of toxic heavy metal from the body as a plausible explanation for the benefits of chelation therapy on heart health.

A recent study20 published in the BMJ used a meta-analysis to demonstrate even low levels of toxic heavy metals pose a risk to your cardiovascular health. Lead study author Rajiv Chowdhury, Ph.D., an associate professor in global health at the University of Cambridge in the U.K., commented:21 

"It's clear from our analysis that there's a possible link between exposure to heavy metals or metalloids and risk of conditions such as heart disease, even at low doses — and the greater the exposure, the greater the risk."

Sauna Use Reduces Your Risk of Multiple Conditions

Sauna use not only reduces your risk of CVD through multiple channels, including detoxifying heavy metal accumulation, but also helps reduce your risk of other health conditions. For example, sauna use has been shown to:

Reduce your risk of stroke22 — Taking a sauna one to three times each week has been shown to lower your stroke risk by 12 percent, while daily sauna use (four to seven times a week) can reduce your risk by as much as 62 percent.

Researchers suggest sauna use reduces stroke risk by lowering inflammation, reducing arterial stiffness and improving blood flow through your circulatory system.

Benefit your brain — By increasing the production of growth factors and brain derived neurotrophic factor,23 sauna use activates brain stem cells to convert into new neurons,24,25 thereby lowering your risk for dementia and Alzheimer's.

Boost your mood — Your body responds to heat through the production of dynorphin,26 the chemical opposite of endorphins. However, dynorphins sensitize your brain to endorphins, which tends to boost mood. If you've ever had a sauna, you've probably experienced this "mellowing" effect.

Improve fitness and athletic performance — Exposure to heat increases your endurance,27 in part by boosting NO. Heat stress also increases plasma volume and blood flow to your heart, which reduces cardiovascular strain and lowers your heart rate during exercise.

Since sauna use increases blood flow to your muscles, it also reduces fatigue, and by improving thermoregulatory control and increasing sweat rate, it allows your core body heat to remain lower, even during intense exertion.

Protect heart health — Exposure to heat improves vascular health, and reduces blood pressure and heart rate.28

Aid detoxification — Flushing toxins out of your body, including pesticides and heavy metals such as cadmium, arsenic, lead and mercury, protects your neurological29 and cardiovascular health.

Boost your immune function — Sauna use increases white blood cell, lymphocyte, neutrophil and basophil counts.

Reduce pain — Infrared saunas may reduce pain associated with rheumatoid arthritis, ankylosing spondylitis30 and fibromyalgia,31 as well as headache pain.

In a study of patients with fibromyalgia, a reduction in pain32 between 33 percent and 77 percent was noted after use of a far infrared dry sauna. Six months after the conclusion of the study, participants continued to report a reduction in pain between 28 percent and 68 percent.

Kill disease-causing microbes.

Lower inflammation and reduce oxidative stress.

Improve respiratory function — Study participants with asthma, bronchitis and obstructive pulmonary disease experienced improved respiratory function after sauna use.33,34

Reduce all-cause mortality.35

Testing for Heavy Metal Toxicity

There are a number of different ways to test for heavy metals, including hair, urine and stool. Certain metals, such as thallium, show up best in a urine dimercaptosuccinic acid (DMSA) challenge test.

DMSA is a chelating agent that can be administered either orally or intravenously. When taken together with a synergistic agent like glycine, it binds to the metals in your body, forcing them out through your stool and urine.

Wendy Myers, a functional diagnostic nutritionist, founder of MyersDetox.com and author of "Limitless Energy: How to Detox Toxic Metals to End Exhaustion and Chronic Fatigue," is a treasure trove of information on the topic of detoxification.

Myers typically starts with a hair mineral analysis as it's easy to do, relatively inexpensive and provides a significant amount of information. Ideally, you'll want to do all three — hair, stool and urine tests — as no one test is perfect. Some metals come out in hair, others in urine and/or stool. Cadmium, for example, comes out in stool, so a stool test will be the most accurate.

General Recommendations for Sauna Use

If you've never used a sauna, start by spending only four or five minutes and work your way up to between 15 and 30 minutes. You will lose important electrolytes when you use a sauna, so it is important to make sure you supplement with salt.

Salt your food with pink Himalayan salt, or put a half-teaspoon in 2 ounces of water and flavor it with lemon or lime juice and use it as salt shot. Even if you can comfortably tolerate the heat, remember the detoxification process can be severe if your toxic load is high.

If you experience detox symptoms or feel ill after sauna bathing, try cutting down on the time spent and slowly work your way up. You'll find a discussion on the different types of saunas in my previous article, "Boost Your Cardiovascular Health and Fitness With Regular Sauna Use." With those considerations, here are some general recommendations for using a sauna:

• Infrared sauna — 160 to 180 degrees F for 15 to 30 minutes
• Regular (Finnish wet or dry) sauna — 180 to 190 degrees F for 10 to 20 minutes

Additionally, consider the following safety tips at all times:

Avoid using a sauna by yourself; always sauna with a buddy.

Listen to your body when deciding how much heat stress you can tolerate. If you're ill or heat-sensitive, decrease the temperature, time spent in the sauna or both.

Do not use a sauna if you've been drinking alcohol.

Be sure to drink plenty of pure water before and after your sauna session. To replace electrolytes use Himalayan salt as discussed above.

Avoid the sauna during pregnancy.

You may want to rest either sitting or lying down for about 10 minutes afterward.