Sauna health benefits: steam or infrared?

Regular sauna sessions can act like “light cardio” for your blood vessels, lowering inflammation and supporting heart health when you use them often and safely. Here is how to get real sauna health benefits without taking unnecessary risks.

The relationship

A sauna is a heated room that raises your skin and core temperature enough to trigger heavy sweating and a faster heart rate. Traditional Finnish saunas heat the air to roughly 70–100 °C. Infrared saunas use light to warm your tissues at lower air temperatures, usually 45–60 °C.

Large population studies from Finland, where sauna bathing is a weekly habit, link regular sauna use to powerful sauna health benefits. In one 20-year study of 2,315 middle-aged men, those who used a sauna 4–7 times per week had a 63% lower risk of sudden cardiac death than men who used it once per week.^[1] The same research group found dose–response benefits for fatal coronary heart disease and death from any cause: more frequent sessions meant lower risk.^[1],[2]

Sauna bathing also tracks with lower levels of chronic inflammation. High-sensitivity C‑reactive protein (hsCRP) is a blood marker of whole-body inflammation that predicts heart disease. In Finnish adults, more frequent sauna use was linked with lower odds of elevated hsCRP levels, suggesting that regular heat exposure may help keep systemic inflammation in check.^[3] Those shifts in inflammation and circulation appear to be key to long-term sauna health benefits.

How it works

To understand sauna health benefits, it helps to know what that heat is doing inside your body. Several overlapping systems are in play: your blood vessels, heart, nervous system, immune system, and muscles all respond.

Heat as “passive cardio” for your heart and vessels

When you sit in a hot room, your skin blood vessels widen. This vasodilation is the medical term for blood vessels opening wider to move more blood. Your heart rate rises, often into the 100–150 beats per minute range, similar to easy to moderate aerobic exercise.^[1] In controlled trials, repeated sauna sessions have improved endothelial function. The endothelium is the thin cell layer lining your blood vessels that controls how they tighten and relax.

This “passive cardio” effect can nudge resting blood pressure down. Small randomized studies in people with high blood pressure and heart failure show that 2–5 weeks of regular sauna or similar heat therapy lowered systolic blood pressure by about 10 mmHg and improved vessel flexibility.^,[4]

Turning down chronic inflammation

Chronic inflammation is long-lasting, low-grade immune activation that quietly damages blood vessels and organs over years. hsCRP is one lab test that tracks this process. Observational studies from sauna cultures link frequent sauna use with lower hsCRP and fewer inflammatory flares over time.^[3]

Part of this anti-inflammatory effect may come from increased expression of heat shock proteins. Heat shock proteins are “chaperone” proteins that help repair damaged cells and protect them from stress. In human and animal experiments, heat exposure boosts these proteins, which can reduce oxidative stress and downstream inflammatory signaling.^[5]

Nervous system reset and stress hormones

Sauna heat activates your sympathetic nervous system, the “fight or flight” branch, during the session. Heart rate and adrenaline rise. Once you cool down, the parasympathetic or “rest and digest” branch rebounds. Over repeated sessions, some people show lower baseline resting heart rates and improved heart rate variability, a marker of more resilient autonomic balance.

Short-term spikes in cortisol, the main stress hormone, are common in the heat. However, studies of regular sauna users suggest that, over weeks, the body becomes less reactive. In practice, many people report better sleep and calmer moods, and early data support small but meaningful improvements on stress and well-being scales after structured sauna programs.^[6]

Muscle recovery and pain relief

For athletes and active adults, one of the most attractive sauna health benefits is better recovery. Heat increases blood flow to muscles, which can speed the removal of metabolic byproducts like lactate and deliver more oxygen and nutrients for repair. Small clinical trials have found that post-exercise sauna sessions can reduce delayed-onset muscle soreness and perceived fatigue compared with passive rest.^[7]

Heat can also modulate pain signaling. Thermal therapy stimulates sensory nerves in the skin that can block deeper pain signals, a process known as “gate control” of pain. In chronic pain conditions such as low back pain or fibromyalgia, multi-week sauna programs have produced reductions in pain scores and improved quality of life, although sample sizes are small and more research is needed.^[8]

Traditional vs infrared: similar benefits, different feel

Traditional Finnish saunas heat the air and then your skin, while infrared saunas use specific light wavelengths to warm you more directly. Infrared rooms feel more tolerable to some people because the air temperature is lower, but your core temperature still rises enough to trigger sweating and cardiovascular responses.

So far, no high-quality head-to-head trials show that infrared saunas provide greater sauna health benefits than traditional dry saunas. Most of the long-term outcome data on heart disease and mortality come from Finnish-style saunas.^[1],[2] Infrared may be a useful option for people who cannot tolerate very hot air, but it should be viewed as an alternative route to similar physiological effects, not a proven upgrade.

Conditions linked to it

Used correctly, sauna bathing is associated with lower risk of several major conditions. Much of the evidence comes from observational studies in Finland, so it shows strong links but not absolute proof of cause and effect.

• Cardiovascular disease and sudden cardiac death: In Finnish men followed for about 20 years, using a sauna 4–7 times per week was linked with roughly 50–60% lower risk of fatal coronary heart disease and sudden cardiac death, compared with once-weekly users.^[1],[2] The pattern suggested that more frequent and longer sessions had greater protective effects.
• All-cause mortality: In the same cohorts, regular sauna users had substantially lower risk of death from any cause. Men taking 4–7 weekly sauna baths had about a 40% lower all-cause mortality than men who used the sauna once per week, even after adjusting for other lifestyle factors.^[2]
• High blood pressure: Hypertension is chronically elevated blood pressure that strains the heart and arteries. Habitual sauna use has been associated with a reduced risk of developing hypertension, and short-term intervention studies show modest drops in blood pressure, particularly in those starting with higher readings.^[3]
• Heart failure and coronary disease symptoms: In patients with stable heart failure or coronary artery disease, supervised heat therapy programs have improved exercise tolerance, reduced angina episodes, and enhanced quality-of-life scores.^[4] These programs often use lower-temperature “waon” (gentle) saunas to keep stress on the heart controlled.
• Cognitive decline and dementia: Finnish data link more frequent sauna use with lower rates of dementia and Alzheimer’s disease over long follow-up. Men using saunas 4–7 times weekly had about 65% lower dementia risk compared with those using them once weekly.^[9] Researchers suspect improved blood flow and reduced vascular risk factors help protect the brain.
• Chronic pain and musculoskeletal issues: Early trials suggest regular sauna sessions can reduce pain and stiffness in conditions such as chronic low back pain, osteoarthritis, and fibromyalgia, though evidence is still limited and often combined with other rehabilitation strategies.^[8]

Limitations note: Most of these findings come from observational studies in one country with strong sauna traditions. People who use saunas often may also eat better, exercise more, and have stronger social networks. While researchers adjust for many of these factors, we cannot fully rule out healthy-user bias. Randomized controlled trials on long-term hard outcomes are still lacking.

Symptoms and signals

Most healthy people tolerate sauna sessions well, especially if they build up gradually. Still, it is important to watch for warning signs that the heat is too much for your body.

• Feeling lightheaded, dizzy, or unsteady when you stand up
• Racing heart that feels uncomfortable, irregular, or “pounding” in your chest
• Chest pain, pressure, or trouble catching your breath
• Nausea, headache, or feeling unusually weak or “foggy”
• Skin that stops sweating despite continued heat exposure
• Muscle cramps, especially in calves, feet, or hands
• Very dark urine or not needing to urinate for many hours after a session
• Needing much longer than usual to cool down and feel normal after leaving the sauna

People with certain conditions should be extra cautious or speak with a clinician before adding regular sauna sessions. These include uncontrolled high blood pressure, unstable angina, severe aortic stenosis, recent heart attack, advanced kidney disease, and pregnancy. Heavy alcohol use before or during sauna time significantly increases the risk of fainting, heart rhythm problems, and even sudden death.

What to do about it

To capture sauna health benefits while keeping risk low, treat heat exposure as a training tool. Dose matters. Frequency, session length, and temperature all add up.

1. Step 1 – Check your baseline and medical risks
   If you have heart disease, uncontrolled high blood pressure, kidney disease, or you are over 60 and new to vigorous heat exposure, talk with your clinician before starting a regular sauna routine. Share your goals, medications, and any symptoms such as chest pain or exercise intolerance. For men concerned about performance or overall vitality, it can also be reasonable to check blood pressure, fasting lipids, and, if symptoms fit, total and free testosterone. Meta-analyses indicate that symptomatic men with total testosterone below 350 ng/dL (≈12 nmol/L) or free testosterone below 100 pg/mL (≈10 ng/dL) are most likely to benefit from testosterone replacement therapy if other causes are excluded.
2. Step 2 – Build a smart, consistent sauna routine
   The strongest sauna health benefits in Finnish cohorts appeared at 4–7 sessions per week.^[1],[2] A practical starting template for healthy adults:
   • Begin with 2–3 sessions per week
   • Keep early sessions at 10–15 minutes, then progress to 20 minutes as tolerated
   • Use moderate heat at first: around 70–80 °C in a traditional sauna, or low to mid settings in infrared
   • Hydrate with water before and after; avoid alcohol completely around sessions
   • Cool down gently with a lukewarm or cool shower; avoid sudden ice plunges until you know your cardiovascular response

   Over time, many people work up to 15–20 minutes per session, 4–5 times per week, which aligns with the dose seen in the Finnish mortality studies.^[1],[2]

3. Step 3 – Monitor your response and adjust
   Track basic markers:
   • Resting heart rate and blood pressure over weeks
   • Sleep quality and energy levels
   • Exercise recovery, soreness, and performance
   • Any episodes of dizziness, palpitations, or feeling unwell in or after the sauna

   If your blood pressure trends down, sleep improves, and you feel fresher between workouts, your current dose is likely working. If you notice persistent fatigue, headaches, or performance drops, you may be overdoing heat exposure or under-replacing fluids and electrolytes.

Myth vs Fact

• Myth: “Infrared saunas are medically superior to traditional saunas for heart health.”
  Fact: Most long-term data on heart and mortality benefits come from traditional Finnish saunas. Infrared offers a different comfort profile, but not clearly superior outcomes so far.^[1],[2]
• Myth: “The sauna ‘detoxes’ heavy metals and clears all toxins from your body.”
  Fact: Sweat does contain trace amounts of metals and chemicals, but your liver and kidneys do almost all detox work. Sauna health benefits are better explained by cardiovascular and anti-inflammatory effects, not miracle detox.^[5]
• Myth: “Longer and hotter sessions are always better.”
  Fact: Benefits appear to follow a sweet spot of moderate heat for 10–20 minutes, done often. Extreme heat or marathon sessions raise the risk of dehydration, fainting, and heart stress without clear added benefit.
• Myth: “People with heart disease should avoid saunas altogether.”
  Fact: Under medical supervision and with gentler protocols, many people with stable heart failure or coronary disease can safely use low-temperature saunas and may gain symptom relief and fitness improvements.^[4]
• Myth: “If you are not dripping sweat, you are not getting any benefit.”
  Fact: Heart rate, vessel dilation, and nervous system changes begin even before heavy sweating. Sweating is one visible marker, not the only sign that your body is responding.

Bottom line

Regular sauna use is one of the few recovery tools backed by long-term data connecting a simple habit to lower risks of heart disease, dementia, and early death. The core sauna health benefits come from how repeated heat trains your blood vessels, calms chronic inflammation, and supports recovery between life’s other stresses. Traditional and infrared saunas can both help, as long as you keep the dose moderate, the sessions consistent, and your safety front and center. For most men, the best sauna is the one you will use several times a week without overdoing it.

References

1. Laukkanen JA, Laukkanen T, Kunutsor SK. Cardiovascular and Other Health Benefits of Sauna Bathing: A Review of the Evidence. Mayo Clinic proceedings. 2018;93:1111-1121. PMID: 30077204
2. Laukkanen T, Khan H, Zaccardi F, et al. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA internal medicine. 2015;175:542-8. PMID: 25705824
3. Laukkanen JA, Laukkanen T. Sauna bathing and systemic inflammation. European journal of epidemiology. 2018;33:351-353. PMID: 29209938
4. Tei C, Horikiri Y, Park JC, et al. [Effects of hot water bath or sauna on patients with congestive heart failure: acute hemodynamic improvement by thermal vasodilation]. Journal of cardiology. 1994;24:175-83. PMID: 8207631
5. Heinonen I, Laukkanen JA. Effects of heat and cold on health, with special reference to Finnish sauna bathing. American journal of physiology. Regulatory, integrative and comparative physiology. 2018;314:R629-R638. PMID: 29351426
6. Kukkonen-Harjula K, Kauppinen K. Health effects and risks of sauna bathing. International journal of circumpolar health. 2006;65:195-205. PMID: 16871826
7. Stanley J, Halliday A, D’Auria S, et al. Effect of sauna-based heat acclimation on plasma volume and heart rate variability. European journal of applied physiology. 2015;115:785-94. PMID: 25432420
8. Matsushita K, Masuda A, Tei C. Efficacy of Waon therapy for fibromyalgia. Internal medicine (Tokyo, Japan). 2008;47:1473-6. PMID: 18703857
9. Heinonen I, Laukkanen JA. Effects of heat and cold on health, with special reference to Finnish sauna bathing. American journal of physiology. Regulatory, integrative and comparative physiology. 2018;314:R629-R638. PMID: 29351426