I design saunas for a living. And the question I get asked more than any other — more than "what wood should I use" or "how big should my sauna be" — is some version of "what about infrared?"

It usually comes with a link to an Instagram reel or a podcast clip where someone with great abs is explaining how their infrared sauna detoxes heavy metals, burns 600 calories, fights cancer, reverses aging, and basically replaces the need for a doctor.

Some of these claims have real research behind them. Some are complete nonsense. And the problem is that the people making the loudest claims almost never distinguish between the two.

So here's my attempt to lay it all out — what the science actually shows, where the evidence is strong, where it falls apart, and what I honestly think about infrared saunas after years of designing them for clients.

This is going to be long. If you want the short version: infrared saunas are probably good for you, especially for pain and cardiovascular health, but they're not magic, and most of the impressive statistics you see online come from research on traditional saunas, not infrared.

How Do Infrared Saunas Work? (Infrared vs Traditional Sauna)

Before we get into the research, it helps to understand what makes infrared different from a traditional sauna. It's simpler than most people think.

A traditional sauna heats the air. You've got a stove — electric or wood-fired — that gets the air temperature up to 150-195°F. You sit in that hot air, your body heats up, you sweat. The heat transfer is mostly convective (hot air touching your skin) and a little bit radiative (heat radiating off the stove and stones).

An infrared sauna uses panels that emit infrared light — electromagnetic radiation in a wavelength your body absorbs directly. The panels heat your body without heating the air as much. Air temperatures in an infrared sauna are typically 100-140°F.

That's the big difference. Lower air temperature, but your body is still getting hot.

Within infrared, there are three wavelength ranges that manufacturers talk about:

• Near-infrared (NIR): 0.7-1.4 micrometers. Penetrates skin the deepest. This is the wavelength range that overlaps with red light therapy research, which is a whole separate topic.
• Mid-infrared (MIR): 1.4-3 micrometers. Middle ground.
• Far-infrared (FIR): 3-100 micrometers. Most common in infrared saunas. Absorbed primarily by water molecules in the top layers of skin. This is what the majority of clinical research has studied.

Some companies sell "full-spectrum" saunas that combine all three wavelengths. We'll get to the marketing around that later.

The physiological response to infrared heat is similar to traditional sauna in many ways. Your core body temperature rises. Heart rate increases — typically to 100-150 beats per minute, similar to moderate exercise. Blood vessels dilate. You sweat. Your body releases heat shock proteins. The cardiovascular system gets a workout.

The main reason this matters: when you see a study about "sauna bathing," you need to know which type of sauna they were studying. Because the most impressive long-term data comes from traditional saunas, not infrared. And that distinction gets blurred constantly in marketing.

Infrared Sauna Health Benefits That Are Actually Supported by Research

Let's go claim by claim. I'll try to be specific about what was actually studied, how strong the evidence is, and where the gaps are.

Are Infrared Saunas Good for Your Heart?

This is the area with the most and best research. But here's where you need to pay attention to which type of sauna was studied.

The gold standard is the Laukkanen research out of Finland. A 2015 study published in JAMA Internal Medicine followed 2,315 Finnish men for over 20 years (Laukkanen et al.). The results were striking: men who used a sauna 4-7 times per week had a 63% lower risk of sudden cardiac death (hazard ratio 0.37) and significantly lower fatal cardiovascular disease risk compared to men who used a sauna once a week. They also had a roughly 40% lower risk of all-cause mortality.

That's a massive effect size. It got a lot of attention.

But here's what matters: these were traditional Finnish saunas operating at an average of 174°F. Not infrared.

Laukkanen and colleagues extended their research in 2018 with a study published in BMC Medicine that included women, and the cardiovascular benefits held up across both sexes. Again — traditional saunas.

So where does infrared fit in? The cardiovascular research specific to infrared saunas is smaller in scale but still meaningful.

Beever published a study in 2009 in the Canadian Family Physician looking at far-infrared sauna use and cardiovascular risk factors. The study found improvements in blood pressure and other markers in patients with cardiovascular risk factors. It's a useful data point but a much smaller study than the Finnish cohort research.

The mechanism that makes scientists think infrared likely provides similar cardiovascular benefits is straightforward: the cardiovascular stress response is similar. Your heart rate goes up. Blood vessels dilate. Blood pressure drops after the session. These acute responses happen regardless of whether the heat comes from hot air or infrared radiation — what matters is that your core temperature rises.

But "likely provides similar benefits" and "proven to provide the same benefits" are different statements. Infrared doesn't have 20-year longitudinal data with thousands of participants. The Finnish studies are remarkable partly because that kind of long-term cohort study is incredibly hard to do.

My honest take: the cardiovascular benefits of infrared are plausible and supported by smaller studies, but anyone who quotes the 50% reduction in fatal CVD number in the context of infrared saunas is borrowing someone else's data.

Infrared Sauna for Heart Failure

This is one area where infrared research stands on its own. And it's genuinely promising.

Ohori and colleagues published a clinical trial in 2012 in the American Journal of Cardiology studying 41 heart failure patients undergoing far-infrared sauna therapy. The results showed that FIR sauna therapy reduced BNP levels (a biomarker for heart failure severity) and improved ejection fraction — meaning the heart was actually pumping more effectively. A later meta-analysis by Hussain et al. in 2018 (Clinical Cardiology, 7 studies, 491 patients) confirmed the pattern across multiple trials.

The protocol in most of these studies was called "Waon therapy" — a Japanese approach using far-infrared saunas at about 140°F for 15 minutes, followed by 30 minutes of bed rest wrapped in blankets. Patients typically did this five days a week for two to four weeks.

The improvements were clinically meaningful. Heart failure patients saw reduced symptoms, better exercise tolerance, and improved cardiac function markers. Several Japanese hospitals have adopted this as a complementary therapy.

This is real. It's not a cure for heart failure, and it doesn't replace standard medical treatment. But as a complementary therapy under medical supervision, far-infrared sauna has some of the strongest evidence of any sauna-specific application.

Infrared Sauna for Chronic Pain

If I had to point to one area where infrared saunas have the clearest, most practical evidence, it's pain management.

A systematic review published in Pain Medicine in 2022 analyzed 12 randomized controlled trials involving 1,047 participants with various chronic pain conditions. The findings showed 40-50% pain reduction across conditions including rheumatoid arthritis, ankylosing spondylitis, fibromyalgia, and chronic lower back pain.

That's a meaningful effect. And unlike some other claimed benefits, this research was done specifically with infrared saunas.

Oosterveld and colleagues published an important study in Clinical Rheumatology in 2009 comparing infrared sauna therapy to traditional sauna therapy for patients with rheumatoid arthritis and ankylosing spondylitis. Both types reduced pain and stiffness during treatment, though the infrared group saw improvements during the treatment period that were statistically significant. Pain and stiffness decreased without worsening disease activity markers.

The mechanisms likely involve a combination of factors: increased blood flow to tissues, reduced muscle tension, decreased joint stiffness from warming, and potentially modulation of pain signaling. There may also be anti-inflammatory effects, though the evidence on that is more preliminary.

The practical implication is real. For people dealing with chronic pain — arthritis, fibromyalgia, chronic back pain — regular infrared sauna use appears to provide meaningful relief. It's not replacing physical therapy or medical treatment, but as part of a pain management approach, the evidence is solid.

Infrared Sauna for Depression and Mental Health

This one is interesting. And it comes from a direction most people don't expect.

Janssen and colleagues published a study in 2016 in JAMA Psychiatry — a well-respected journal — looking at whole-body hyperthermia as a treatment for major depressive disorder. A single session of raising core body temperature to about 101.3°F produced significant antidepressant effects that lasted for six weeks.

The study was small (n=34) and used a specialized hyperthermia device rather than a consumer sauna, but the results were compelling enough to generate serious interest in the research community.

A follow-up trial at UCSF reported that 86.2% of participants no longer met the diagnostic criteria for major depressive disorder after repeated whole-body hyperthermia treatments. That's a remarkable response rate, though it's important to note these are still relatively small clinical trials.

The proposed mechanism involves serotonin pathways. Warming the skin activates thermosensory pathways that project to brain regions involved in mood regulation. There may also be effects on inflammatory markers, which are increasingly linked to depression.

The broader epidemiological data from Finland supports this too. The Laukkanen studies found that frequent sauna use was associated with lower risk of psychotic disorders, and other Finnish research has linked sauna bathing to reduced risk of dementia and Alzheimer's disease.

Here's my honest assessment: the mental health data is promising and comes from credible sources. But these are still early-stage clinical trials. We're a long way from being able to say "infrared saunas treat depression" with the same confidence we can say "infrared saunas help with chronic pain." The mechanism is plausible, the initial results are encouraging, and larger trials are needed.

That said, most people who use a sauna regularly will tell you it improves their mood. Whether that's the heat, the forced stillness, or some combination, the subjective experience is pretty consistent.

Infrared Sauna for Muscle Recovery

Athletes and fitness enthusiasts are a huge market for infrared saunas, so the recovery claims deserve scrutiny.

Ahokas and colleagues published a study in 2023 in Biology of Sport looking at post-exercise far-infrared sauna use. The study found that FIR sauna bathing after exercise improved neuromuscular recovery and attenuated muscle soreness compared to passive recovery alone.

The effect was real but modest. We're not talking about dramatically accelerated recovery — more like taking the edge off soreness and getting you back to baseline a little faster.

Other studies have looked at heat acclimation benefits from sauna use, which can improve endurance performance. But most of that research has been done with traditional saunas, and the protocols typically involve higher temperatures than what an infrared sauna provides.

The practical takeaway: using an infrared sauna after a hard workout probably helps a bit with recovery. It's not going to transform your training, but it's a pleasant way to wind down that has some evidence behind it. Just make sure you're hydrating properly — adding dehydration to post-exercise recovery is counterproductive.

Infrared Sauna Claims That Don't Hold Up

Now for the part that makes the infrared sauna industry uncomfortable. Because some of the most popular claims about infrared saunas range from exaggerated to flat-out wrong.

Do Infrared Saunas Detox Your Body?

This is the big one. "Infrared saunas detox your body" is probably the single most common marketing claim in the industry. And it's mostly nonsense.

The study that gets cited most often is the BUS study by Genuis and colleagues, published in 2011. They analyzed sweat and found that it contained trace amounts of heavy metals including arsenic, cadmium, lead, and mercury. This is real — sweat does contain trace metals.

But here's what the detox marketers leave out: the amounts are tiny. Your liver and kidneys handle 99%+ of your body's detoxification processes. The amount of toxins you excrete through sweat is negligible compared to what your liver processes in an hour.

"Detox" is a red flag word in medical science. When researchers talk about detoxification, they're talking about specific enzymatic pathways in the liver and filtration in the kidneys. When marketers talk about detox, they're usually selling something.

Can you excrete some trace amounts of certain substances through sweat? Yes. Is it a meaningful detoxification pathway that justifies buying a $5,000 sauna? No.

Your body already has a detox system. It's called your liver and kidneys. If those are functioning normally, you don't need a supplemental detox method. If they're not functioning normally, you need a doctor, not a sauna.

I'm not saying there's zero benefit to sweating. There may be minor benefits to excreting certain substances through the skin. But the degree to which this has been exaggerated by the infrared sauna industry is embarrassing. If someone leads their marketing with "detox," I'd take everything else they say with a large grain of salt.

Can You Lose Weight in an Infrared Sauna?

The claim usually goes something like: "Burn up to 600 calories in a single 30-minute infrared sauna session."

No. You don't.

The one study that weight loss claims typically trace back to was done at Binghamton University and had serious methodological issues — it didn't adequately control for diet or exercise changes in participants.

The reality: sitting in a sauna does burn some calories because your body has to work to cool itself down. But the calorie expenditure is much closer to a brisk walk than to a serious workout. Estimates vary, but you're probably looking at 50-80 additional calories above your resting metabolic rate during a typical session. Not 600.

The weight you lose during a sauna session is water. You sweat it out, you drink water afterward, and the weight comes back. This isn't controversial — it's basic physiology.

Can regular sauna use be part of a healthy lifestyle that includes weight management? Sure. But claiming infrared saunas burn 600 calories per session is the kind of claim that undermines the industry's credibility on everything else.

Cancer Treatment or Prevention

I need to be direct about this: there is zero clinical evidence that infrared saunas treat, cure, or prevent cancer.

The FDA has taken action against infrared sauna manufacturers who have made cancer-related claims. This isn't a gray area. It's dangerous misinformation.

Some people point to research on hyperthermia as a cancer treatment — heating tumors can make them more susceptible to radiation and chemotherapy. This is a legitimate medical technique, but it's done in clinical settings with precise temperature control targeting specific tumor sites. It has nothing to do with sitting in a consumer infrared sauna.

If someone is selling you an infrared sauna with cancer claims, walk away. They're either uninformed or deliberately misleading you, and either way you shouldn't trust their product recommendations.

Anti-Aging

The anti-aging claims are based on a few small in vitro studies — meaning they were done on cells in a lab, not on actual humans — showing that certain wavelengths of infrared light can stimulate collagen production in skin cells.

That's interesting preliminary science. It is not evidence that sitting in an infrared sauna reverses aging.

There's a big gap between "infrared light stimulated collagen production in a petri dish" and "infrared saunas make you look younger." Until there are controlled clinical trials showing measurable anti-aging effects from infrared sauna use in actual people, this remains speculation.

Immune System Boosting

Heat shock proteins are real. Your body produces them in response to heat stress, and they play important roles in cellular repair and protection. Sauna use does increase heat shock protein production.

But "heat shock proteins are produced" and "your immune system is boosted" are different claims. The clinical significance of increased heat shock protein production from sauna use hasn't been established in a way that translates to "you'll get sick less often" or "your immune system will be stronger."

There is some epidemiological data from Finland suggesting that frequent sauna users get fewer colds, but this is associational data with confounding variables. People who use saunas 4-7 times per week may differ from once-a-week users in many ways beyond sauna frequency.

The honest answer: heat stress probably does have some immune-modulating effects. Whether those effects are clinically meaningful for a healthy person is unproven.

"Full-Spectrum is Better Than Far-Infrared"

This is pure marketing.

There is no comparative clinical data showing that full-spectrum infrared saunas (combining near, mid, and far wavelengths) produce better health outcomes than far-infrared-only saunas. None.

The companies selling full-spectrum saunas at premium prices are making an engineering claim (we include more wavelengths) and implying a health benefit that hasn't been studied. The vast majority of infrared sauna research has been done with far-infrared panels. If you're buying based on evidence, far-infrared has the most research behind it.

Near-infrared therapy does have its own body of research, mostly from the red light therapy and photobiomodulation literature. But that research typically uses specific wavelengths at specific intensities applied directly to tissue — not panels at the back of a sauna box several feet from your body.

I'm not saying full-spectrum saunas are bad products. I'm saying the "full-spectrum is scientifically superior" claim doesn't have research behind it. It's a marketing differentiator, not a scientific conclusion.

The Elephant in the Room

Here's the thing that the infrared sauna industry really doesn't want you to think too carefully about.

The most impressive, most frequently cited sauna health statistics — the 50% reduction in fatal cardiovascular disease, the reduced dementia risk, the all-cause mortality benefits — all come from Finnish studies on traditional saunas. Not infrared.

The Laukkanen studies used traditional Finnish saunas operating at 174°F and above. The participants sat in hot rooms heated by sauna stoves, often with steam from throwing water on stones. These are fundamentally different devices from an infrared sauna cabinet.

Infrared sauna manufacturers benefit enormously from this conflation. When you see a website that says "studies show sauna use reduces cardiovascular disease by 50%" next to a picture of their infrared product, they're borrowing credibility from research that wasn't done on their product.

This doesn't mean infrared saunas don't work. It means the evidence base is different and generally smaller.

And there's another piece of uncomfortable data: a 2025 meta-analysis examining the effects of passive heating (which includes infrared sauna) on cardiometabolic markers found that passive heating did not significantly improve key cardiometabolic measures. This matters because it challenges some of the cardiovascular benefit assumptions that have been extended from traditional sauna research to infrared.

The difference might come down to the intensity of the heat stress. Traditional saunas at 174-195°F create a more intense cardiovascular challenge than infrared saunas at 120-140°F. Higher heat stress may drive larger adaptations. This is speculative, but it's a plausible explanation for why the traditional sauna data is more impressive.

The research community is aware of this gap. There are calls for more long-term studies specifically on infrared sauna use. But right now, the honest statement is: infrared saunas probably provide cardiovascular benefits through similar mechanisms to traditional saunas, but we don't have the long-term data to confirm that.

So Why Do I Still Design and Recommend Infrared Saunas?

After all that skepticism, you might wonder why I still design infrared saunas for clients. Fair question.

The main reason is that accessibility matters.

Not everyone can handle a traditional sauna at 175°F. People with certain health conditions, older adults, people who are heat-sensitive, people who are new to sauna and find 170°F intimidating — infrared gives them a way to get regular heat exposure at temperatures they can tolerate.

A sauna that someone actually uses three or four times a week at 130°F is going to do more for them than a traditional sauna they bought but barely use because they find it overwhelming.

Beyond accessibility, here's what I think the evidence genuinely supports for infrared:

Pain relief is real. The systematic review covering 12 RCTs and over a thousand participants is solid evidence. If you're dealing with chronic pain — arthritis, fibromyalgia, chronic back pain — regular infrared sauna use is a reasonable, low-risk intervention with good evidence behind it.

The heart failure data is promising. Waon therapy using far-infrared saunas has shown real clinical benefit for heart failure patients. This is being used in actual hospitals.

The cardiovascular stress response is similar. Even though we don't have 20-year longitudinal data for infrared, the acute physiological responses — heart rate elevation, vasodilation, blood pressure reduction — are comparable to traditional sauna at more comfortable temperatures. It's reasonable to expect some degree of cardiovascular benefit from regular use.

It's a pleasant, low-risk activity. For most healthy people, using an infrared sauna regularly is safe and enjoyable. Even if the health benefits turn out to be more modest than the marketing suggests, the downside risk is minimal.

The mental health benefits, while not fully proven, are plausible. Whole-body hyperthermia shows promising results for depression. Regular sauna users consistently report mood improvements. Whether infrared is as effective as traditional sauna for these benefits is unknown, but the subjective experience is positive.

The trade-off with infrared is that you're likely getting a milder version of the heat stress response compared to traditional sauna. For some people, that's exactly what they want. For others, especially those chasing the cardiovascular benefits shown in the Finnish studies, a traditional sauna might be the better choice.

When clients ask me which type to get, I ask them about their goals, their heat tolerance, their space, and their budget. There's no universal right answer. But I never recommend an infrared sauna by telling someone it will detox their body or burn 600 calories per session. That's not how I do business.

Infrared Sauna Side Effects and Who Should Avoid Them

Infrared saunas are generally safe for healthy adults. But "generally safe" isn't the same as "safe for everyone."

Talk to your doctor first if you have:

• Unstable cardiovascular conditions, including unstable angina, recent heart attack, or uncontrolled heart failure
• Very low blood pressure or orthostatic hypotension
• Multiple sclerosis or other conditions affected by heat
• Active infections with fever

Avoid infrared saunas if you're:

• Pregnant. The concern is elevated core body temperature, especially during the first trimester. There isn't enough safety data, and the potential risk to fetal development isn't worth it.
• Taking medications that affect sweating, blood pressure, or heat regulation. This includes some antihistamines, diuretics, beta-blockers, and others. Check with your prescribing physician.
• Under the influence of alcohol. This sounds obvious but it comes up more than you'd think. Alcohol impairs your body's thermoregulation. Combining it with sauna use increases risk of dehydration, dangerous blood pressure drops, and cardiac events.

Common side effects that are normal but worth knowing about:

• Dehydration. This is the most common issue and it's entirely preventable. Drink water before, during, and after your session.
• Lightheadedness when standing up, especially when you first start using a sauna. This is from vasodilation and is usually temporary. Stand up slowly. If it persists, shorten your sessions.
• Mild headache, usually from dehydration.
• Temporary redness of the skin, which resolves within an hour.

For safe use:

• Start with shorter sessions (15-20 minutes) and lower temperatures until you know how your body responds
• Stay hydrated — 16-24 ounces of water before a session, and replenish during and after
• Don't use a sauna if you're feeling unwell
• Listen to your body. If you feel dizzy, nauseous, or uncomfortable, get out

The risks of infrared sauna use are genuinely low for most people. But they're not zero, and anyone selling you on the idea that infrared saunas have no risks is oversimplifying.

A Note on Choosing an Infrared Sauna

I'm not going to turn this into a buying guide — that's a separate post. But a few things worth mentioning in the context of the science discussion:

EMF concerns. You'll see a lot of marketing around "low EMF" infrared saunas. The electromagnetic field emissions from infrared panels are a concern that some manufacturers have addressed with better shielding and panel design. The scientific evidence for health effects from the EMF levels typical of infrared saunas is limited, but if you're spending several thousand dollars, choosing a model with low EMF emissions seems reasonable.

Carbon vs. ceramic heaters. Carbon panels generally produce more even heat distribution across a larger surface area. Ceramic heaters produce more intense, focused heat. Most modern infrared saunas use carbon panels. Both work.

Size matters for usage. The number one factor in whether someone actually uses their sauna regularly is convenience. A sauna that's easy to access, heats up quickly, and is comfortable to sit in for 30-40 minutes gets used. An inconvenient one doesn't. Think about where it's going and whether you'll actually use it before worrying about which wavelength combination is optimal.

The Bottom Line

Here's where I land after reviewing the evidence.

The things that hold up: cardiovascular stress from heat exposure is probably beneficial. Chronic pain relief from infrared sauna use is well-supported by multiple randomized controlled trials. Heart failure patients may benefit significantly from far-infrared sauna therapy under medical supervision. The mental health data is early but comes from credible sources and shows promise.

The things that don't hold up: detoxification claims are wildly exaggerated. Weight loss numbers are fabricated. Cancer claims are dangerous and baseless. Anti-aging benefits are unproven in humans. "Full-spectrum is better" is marketing, not science.

The thing most people miss: the most impressive sauna health statistics come from traditional Finnish sauna research, not infrared research. Infrared likely works through similar mechanisms at lower, more accessible temperatures, but the long-term data isn't there yet. A 2025 meta-analysis finding that passive heating didn't improve cardiometabolic markers adds an important note of caution.

If someone tells you an infrared sauna will detox your body and cure cancer, they're selling something. If they tell you regular heat exposure is probably good for your heart and definitely helps with pain, the evidence supports that.

The honest case for infrared saunas isn't about miracle cures. It's about a pleasant, low-risk activity that has genuine evidence behind it for specific benefits — especially pain management and cardiovascular health — at temperatures that more people can tolerate than traditional saunas.

Use it regularly. Stay hydrated. Don't expect miracles. And don't skip your doctor.

If you're also wondering about red light therapy panels — a related but different topic — I wrote a separate deep dive: Does Red Light Therapy Work? What Science Actually Shows.

Frequently Asked Questions

Do infrared saunas actually work? Yes, but not for everything the internet claims. The strongest evidence supports infrared sauna benefits for chronic pain relief (40-50% pain reduction across 12 randomized trials) and cardiovascular health. The detox and weight loss claims are heavily exaggerated.

Are infrared saunas better than traditional saunas? Not necessarily. Traditional saunas have far more long-term research behind them, including the landmark Finnish studies linking frequent sauna use to significantly lower cardiovascular mortality. Infrared operates at lower, more comfortable temperatures (100-140°F vs 150-195°F), which makes it more accessible. Both likely work through similar heat-stress mechanisms, but the research base for traditional saunas is much deeper.

What are the dangers of infrared saunas? For most healthy adults, the risks are low. The main concerns are dehydration, lightheadedness, and heat exhaustion from overdoing it. People who are pregnant, have unstable cardiovascular conditions, or take medications that affect blood pressure or thermoregulation should consult their doctor first.

How long should you sit in an infrared sauna? Most studies used sessions of 15-30 minutes at temperatures of 120-140°F. If you're new to infrared saunas, start with 15-20 minutes and work up. The Laukkanen research found that longer sessions (over 19 minutes) were associated with greater cardiovascular benefits, though those studies used traditional saunas.

How often should you use an infrared sauna? The Finnish research showed a clear dose-response relationship — more frequent use was associated with greater benefits (4-7 times per week vs once a week). Most clinical studies on infrared saunas used protocols of 3-5 sessions per week. Consistency matters more than individual session length.

Can infrared saunas help with weight loss? Not in any meaningful way. The weight you lose during a session is water weight from sweating, which returns when you rehydrate. Claims of "burning 600 calories per session" are not supported by evidence. Real calorie expenditure above resting is closer to what you'd burn on a brisk walk.