Which Sauna Is Better: Infrared or Steam?

Neither infrared nor steam saunas are categorically better. They deliver heat through fundamentally different mechanisms, produce overlapping but distinct physiological responses, and suit different goals. Most of the cardiovascular and recovery research has been conducted on traditional Finnish-style dry saunas or far-infrared units, with steam rooms receiving considerably less clinical attention. The honest answer is that the “better” sauna depends on what you are trying to accomplish, and the research suggests neither type has a monopoly on health benefits.

How the Heat Actually Reaches You

The core difference between these two experiences is the way thermal energy enters your body. A steam room (sometimes called a steam sauna or wet sauna) fills an enclosed space with moist air, usually around 40 to 50°C with humidity approaching 100 percent. You absorb heat mainly through convection and the condensation of water vapor on your skin. That heavy moisture makes the air feel hotter than the thermometer reads, which is why even moderate temperatures in a steam room can feel intense.

An infrared sauna operates at much lower air temperatures, usually between 45 and 60°C, with minimal humidity. Instead of heating the surrounding air, infrared panels emit radiant energy in the far-infrared spectrum that is absorbed directly by skin and superficial tissue. Your core temperature still rises, and you still sweat, but the path to getting there feels quite different. Many people who find traditional or steam saunas stifling tolerate infrared sessions more comfortably, simply because the ambient air is not as oppressive.

Traditional Finnish saunas sit between the two. They use a stove or electric heater to push air temperatures to 80–100°C at low baseline humidity, though users commonly throw water on hot rocks to create bursts of steam. Much of the published research on “sauna bathing” refers to this Finnish tradition. When a study says “sauna,” it rarely means infrared unless it names far-infrared or Waon therapy specifically, and it almost never means a pure steam room. That distinction matters when you try to apply findings to the sauna in your gym or home.

Cardiovascular Effects

Heart and blood vessel responses are the most studied area for sauna use in general, and the findings are encouraging, with some important caveats. A single session of Finnish sauna bathing has been shown to reduce pulse wave velocity (a marker of arterial stiffness) from about 9.8 to 8.6 meters per second, while systolic blood pressure dropped from 137 to 130 mmHg and diastolic pressure fell from 82 to 75 mmHg. Those improvements partly persisted even 30 minutes after leaving the sauna.¹ Longer-term passive heat therapy over eight weeks has produced even more striking results in sedentary people: improved blood vessel dilation, reduced arterial stiffness, and a drop in mean arterial blood pressure from roughly 83 to 78 mmHg.²

Before extrapolating too broadly, though, a randomized controlled trial of Finnish sauna bathing in adults with established coronary artery disease found no improvement in vascular stiffness, endothelial function, or blood pressure after eight weeks of four sessions per week. The participants did show signs of heat acclimation, including reduced resting core temperature and improved sweating capacity, but those adaptations did not translate to measurable vascular gains.³ The takeaway is that sauna bathing appears to benefit cardiovascular markers in otherwise healthy or sedentary people more reliably than in those who already have advanced heart disease.

Where does this leave infrared versus steam specifically? Most of the cardiovascular data comes from Finnish-style dry saunas or from hot-water immersion protocols, not from infrared panels or dedicated steam rooms. The physiological stimulus, raising core temperature and triggering peripheral vasodilation, is common to all heat modalities. Whether infrared achieves the same vascular benefits at its lower operating temperatures has not been tested head-to-head against steam in controlled cardiovascular trials. If your main goal is cardiovascular conditioning, the available evidence supports regular heat exposure in general without clearly favoring one format over another.

Pain Relief and Muscle Recovery

Infrared saunas have a genuine edge in the pain and recovery literature, largely because of a body of work on a Japanese protocol called Waon therapy. Waon therapy involves sitting in a far-infrared sauna set to about 60°C for 15 minutes and then resting under blankets for an additional 30 minutes to maintain elevated core temperature. In a study of patients with fibromyalgia, all participants experienced a significant reduction in pain, roughly halved after the very first session, and the effect stabilized after about 10 sessions. Pain scores remained low throughout the follow-up observation period.⁴

For athletes, a study comparing post-exercise infrared sauna sessions to a passive rest period found that infrared exposure reduced muscle soreness and improved perceived recovery after resistance training. Participants in the infrared group also showed less decline in explosive performance compared to those who simply rested.⁵ This is one area where the infrared sauna has specific evidence behind it rather than borrowing from Finnish-style or general heat research.

Steam rooms have not been studied with the same rigor for pain or recovery. The moist heat in a steam room can feel soothing on stiff joints and muscles, and many people report subjective relief, but controlled studies demonstrating that steam specifically outperforms dry heat for musculoskeletal recovery are hard to find. If you are dealing with chronic pain conditions or trying to bounce back from a hard workout, infrared has the stronger evidence base right now.

Respiratory Benefits and Steam’s Advantage

This is where steam rooms pull ahead. Breathing warm, humidified air has a direct physiological benefit for your airways that dry heat cannot replicate. Research has shown that warm humidified air substantially reduces bronchoconstriction triggered by body cooling, effectively compensating for the airway narrowing that cold or dry environments can cause.⁶ For anyone prone to exercise-induced airway tightness, or for people who simply want to ease congestion and open up their sinuses, the moisture in a steam room provides a benefit that an infrared sauna’s dry environment does not.

If you have ever sat in a steam room with a stuffy nose and felt it clear within minutes, that is not just subjective. The combination of heat and moisture thins mucus, improves mucociliary clearance, and reduces the irritation that dry air can cause in sensitive airways. Infrared saunas, by contrast, produce very dry air, which some people with reactive airways may actually find mildly irritating during a session. For respiratory comfort specifically, steam wins in a straightforward way.

The Detox Question

Claims that saunas “detoxify” your body by flushing out heavy metals and environmental chemicals are among the most popular selling points for both types, and also among the most overstated. Sweat does contain trace amounts of heavy metals. A systematic review found that arsenic, cadmium, lead, and mercury can be excreted through sweat at rates that sometimes match or exceed urinary excretion over a 24-hour period.⁷ That sounds impressive until you consider the quantities involved: the absolute amounts are tiny, and the body’s primary detoxification organs remain the liver and kidneys by an enormous margin.

A study comparing sweat produced by exercise to sweat produced by passive sauna sitting found that exercise-induced sweat contained significantly higher concentrations of nickel, lead, copper, and arsenic than sauna sweat.⁸ In other words, if your goal is to clear heavy metals through sweat, going for a run appears to be more effective than sitting in any sauna. Neither infrared nor steam sauna advocates can honestly claim a meaningful detoxification advantage over the other, or over simply exercising and letting your liver do its job. The detox narrative sells memberships and home units, but the science behind it is thin regardless of which sauna type you choose.

How the Two Types Affect Your Nervous System

A comparative study in obese individuals put the physiological differences between steam and dry sauna into sharper focus. When researchers measured changes in heart rate variability, a marker of autonomic nervous system activity, both modalities raised heart rate, but the patterns diverged. The steam bath group showed more changes in time-domain heart rate variability measures related to parasympathetic tone, while the dry sauna group produced broader changes including shifts in blood pressure, basal metabolic rate, and frequency-domain variability components like very low frequency, low frequency, and high frequency power. When the two groups were compared directly, significant differences emerged in diastolic blood pressure and several heart rate variability metrics.⁹

What this means in practical terms is that your body does not treat these two heat exposures as identical stressors. The dry sauna (which shares more in common with infrared than with steam, in terms of low humidity) appears to activate a broader stress response and push the cardiovascular and autonomic systems harder. Steam, with its gentler absolute temperatures and moisture-mediated heat transfer, shifts autonomic balance somewhat differently. Neither pattern is inherently better, but the distinction matters if you are trying to use sauna sessions for specific recovery or stress management goals.

Brain Chemistry and Mood

Repeated heat exposure has been linked to improvements in mental health markers that go beyond simple relaxation. A randomized controlled trial comparing whole-body hyperthermia sessions to a low-intensity control found that participants who underwent repeated heating had significantly higher circulating levels of Brain Derived Neurotrophic Factor (BDNF), a protein involved in neural growth and mood regulation. After 24 sessions, the heat group’s BDNF levels rose well above baseline, and the improvements were accompanied by reduced anxiety and better self-reported quality of life.¹⁰

This research used whole-body heating rather than a specific sauna type, so the benefit appears to be linked to core temperature elevation itself rather than to any particular heating method. Both infrared and steam saunas raise core temperature, so either could theoretically deliver similar neurobiological effects with regular use. The mood and anxiety improvements are one of the more compelling reasons to adopt a sauna habit regardless of the format you prefer.

Immune Response to a Single Session

A single Finnish sauna session is enough to trigger a measurable immune response. In a study comparing trained athletes with non-athletes, one session increased white blood cell counts, including lymphocytes, neutrophils, and basophils, in both groups. Athletes showed greater increases in total leukocyte and monocyte counts compared to untrained participants, suggesting that regular physical conditioning may amplify the immune response to heat. Cortisol levels rose significantly in the non-athlete group, indicating that untrained individuals experienced the heat as a greater physiological stressor.¹¹

Once again, this research used a traditional dry sauna rather than steam or infrared specifically. The immune stimulus appears to come from the rise in core body temperature and the mild physiological stress of heat exposure. There is no published evidence that steam saunas produce a stronger or weaker immune response than infrared, and the mechanism suggests both would work as long as core temperature rises sufficiently.

Fluid Loss and the Weight Question

People commonly notice the scale dropping after a sauna session and wonder whether that reflects real weight loss. It does not. A study of young sedentary men measured an average fluid loss of about 0.65 kilograms after four 10-minute dry sauna sessions with breaks in between. Heart rate climbed progressively through the sessions, averaging about 98 beats per minute during the first round and reaching roughly 133 beats per minute by the fourth.¹² A larger study of over 670 young adults found that overweight and obese individuals lost the most body mass per session, while underweight participants lost the least.¹³

All of this weight is water, and it returns the moment you rehydrate. Steam rooms may feel like they produce heavier sweating because the humid air prevents sweat from evaporating, so it pools on your skin more visibly. Infrared saunas let sweat evaporate more efficiently because the air is dry, which means you may actually feel drier even though your sweat rate is comparable. Neither type produces meaningful fat loss from sitting alone. The calorie burn from a sauna session exists but is modest relative to actual physical activity.

Hygiene, Safety, and Practical Tradeoffs

Steam rooms carry specific hygiene concerns that infrared saunas largely avoid. The warm, perpetually moist surfaces of a steam room create an ideal environment for fungal growth. Studies of public bathing facilities have found mould and fungal species on floors, seating surfaces, and personal items like slippers. Beyond fungi, steam-generating systems can harbor Legionella bacteria if not properly maintained. In the Netherlands, six cases of Legionnaires’ disease were traced to a single sauna facility, resulting in two deaths.¹⁴ These risks apply primarily to public steam rooms and are manageable with proper cleaning and water-system maintenance, but they are worth knowing about.

Infrared saunas, because they operate in dry conditions, present far fewer opportunities for microbial colonization. The wooden interiors still need regular cleaning, but the absence of standing moisture eliminates most of the fungal and bacterial concerns that plague steam rooms. If you are evaluating home installation, infrared units are also simpler to set up. They typically plug into a standard electrical outlet, do not require plumbing or a steam generator, and reach operating temperature within 15 to 20 minutes. Steam rooms require waterproof construction, drainage, a dedicated steam generator, and considerably more maintenance to prevent mold and mineral buildup.

From a safety standpoint, both types call for the same baseline precautions: stay hydrated, limit session length (15 to 20 minutes is a reasonable ceiling for most people), and avoid alcohol before or during use. People with unstable cardiovascular conditions should consult a doctor before starting any regular sauna routine, especially given the mixed results seen in the coronary artery disease trial mentioned earlier. Pregnant women are generally advised to avoid both types. Heat exposure raises core temperature regardless of the delivery method, and the fetal risks are the same whether the heat comes from infrared panels or from steam.

When to Choose Which

Rather than one being universally superior, each type has a clearer case in specific situations. If you are dealing with chronic pain, fibromyalgia, or post-workout muscle soreness, infrared saunas have the most direct research support. If your main interest is opening up your airways, clearing congestion, or easing exercise-induced bronchoconstriction, steam rooms provide a benefit that dry-heat environments simply do not. For cardiovascular conditioning, mood improvement, and immune stimulation, the evidence suggests that core temperature elevation is the key driver, which both formats deliver.

Cost and convenience tilt toward infrared for home use. A basic infrared sauna cabin can fit in a spare closet and costs a fraction of what a steam room installation requires. Public facilities tend to offer steam rooms more commonly than infrared saunas, so if you prefer steam, a gym or spa membership may be the most practical route. Some people simply prefer the sensation of one over the other, and consistency matters more than format. A sauna you actually use three times a week will outperform the “optimal” one that sits unused. Personal comfort, your specific health goals, and whether you have access to a well-maintained unit are the factors that should drive the decision rather than any blanket ranking of one type over another.