What actually matters when choosing an infrared sauna
If you've ever looked at buying or renting an infrared sauna, you'll know how confusing the market has become.
Full spectrum.
Far infrared.
Near infrared.
Carbon heaters.
Ceramic heaters.
Low EMF.
Red light.
Detox.
65°C.
70°C.
The list goes on.
But how much of it actually matters?
We've been looking at this closely at Recovery On Demand because we rent infrared saunas, and frankly, some of the marketing in the industry has made us ask better questions about our own.
So here's what we've learned.
Infrared isn't just infrared
An infrared sauna uses infrared energy to heat the body, rather than relying mainly on hot air like a traditional sauna.
But there are different parts of the infrared spectrum.
You'll commonly see:
Near infrared (NIR)
Mid infrared (MIR)
Far infrared (FIR)
A "full spectrum" sauna generally combines more than one of these.
Sounds good.
But here's the catch:
Full spectrum doesn't tell you everything.
It doesn't tell you how much energy is being delivered, where the heaters are positioned, how close you are to them, or how evenly your body is exposed.
So when someone tells you a sauna is "full spectrum", we'd ask:
What wavelengths? At what output? And where are the emitters?
Carbon vs ceramic: which is better?
This is another area where the marketing can get carried away.
Carbon panels are common in modern infrared cabins. They spread heat across a larger surface and can create a more even, gentle experience.
Ceramic and other point-source heaters can produce more concentrated radiant heat.
But there isn't a simple answer that says one is always better.
The design matters more than the label.
Where are the heaters?
Behind you?
Beside you?
In front of your legs?
Under the bench?
How much of your body do they actually reach?
A very good heating element in the wrong place isn't necessarily a very good sauna.
Distance matters too
This is one of those details that often gets missed.
With radiant heat, distance, angle, emitter size and positioning all affect the exposure you receive.
Think about sitting beside a fire.
Move closer and you feel more heat.
Move away and you feel less.
A sauna isn't quite as simple as a campfire, but the principle is useful.
That's why two cabins using similar heating technology can feel very different.
And it's why we think a good sauna specification should tell you more than simply:
"Carbon heaters."
Tell me where they are and how the cabin is designed around them.
Our own sauna, for example, uses emitters across the rear, sides, under the bench/floor and front area. The aim is to create more consistent whole-body coverage rather than having all the heat coming from one direction.
What does "low EMF" actually mean?
This is probably one of the most misunderstood claims in the industry.
You'll see:
Low EMF
Ultra-low EMF
Near-zero EMF
But then ask:
Measured how?
If somebody gives you a reading of 0.3 mG, that's only useful if you know where the meter was.
Was it touching the heater?
10cm away?
50cm away?
At the user's chest?
Was the sauna switched on?
What meter was used?
Was magnetic field being measured, electric field, or both?
These details matter.
Field strength changes with distance from the source, and measurements inside a sauna can vary considerably depending on where the meter is positioned.
This is something Phil Learney has been particularly good at highlighting across the wellness industry: don't be impressed by a precise number if nobody tells you how the number was produced.
So if EMF matters to you, don't just ask:
"Is it low EMF?"
Ask:
"Can I see the measurement methodology?"
That's a much better question.
And then there's red light
Some infrared saunas now include red and near-infrared light.
Interesting?
Yes.
Automatically the same as red-light therapy?
No.
Photobiomodulation research looks at specific things such as wavelength, irradiance, energy density and exposure time.
So if someone tells you their sauna provides red-light therapy, ask:
What wavelength?
What intensity?
At what distance?
For how long?
Simply putting red LEDs inside a sauna doesn't tell you the therapeutic dose.
We're not saying red light doesn't work.
There is a growing body of research around photobiomodulation.
We're saying the specification matters.
Does infrared sauna actually have health benefits?
There is legitimate research here.
Far-infrared sauna has been studied in humans, particularly around cardiovascular and other health outcomes. Researchers including Richard Beever have reviewed the evidence and found some promising results, while also pointing out that the research base is still relatively small. [1]
There's also a long-running body of research around sauna bathing more generally, particularly from Finland, as well as Japanese research into structured heat therapy such as Waon therapy. [2][3]
But there's an important distinction.
The research looks at specific heat exposures and protocols.
It doesn't mean that every sauna labelled "infrared" or "full spectrum" produces the same physiological stimulus.
So again:
Don't just look at the label. Look at what you're actually being exposed to.
What about "detox"?
This is where we need to be more careful.
We've used the word detox in our own sauna marketing.
After digging further into the evidence, we'd now use it much more cautiously.
Yes, sweat contains certain substances that the body is eliminating.
But finding something in sweat isn't the same as proving that sitting in a sauna meaningfully reduces your body's overall toxic burden.
A review of sweat physiology concluded that the body's major detoxification and elimination systems remain the kidneys, liver and gut, and that the contribution of sweating to eliminating many environmental chemicals appears to be small. [4]
Another study looking at heavy metals found that several were actually higher in sweat during exercise than during a sauna session. [5]
Phil Learney recently asked the infrared sauna industry a very simple question:
"Which toxin, exactly?"
It's a fair question.
And honestly, it's one we think consumers should ask us too.
If you have a genuine concern about mold, heavy metals or another environmental exposure, the sensible starting point isn't simply sweating more.
Find out what you're actually dealing with.
Testing, identifying the source of exposure and getting appropriate professional advice makes considerably more sense than assuming a sauna will "flush everything out."
A sauna can be part of a healthy routine.
We just don't think it should be sold as a magic detox box.
What do actual sauna users say?
This is where things get interesting.
Spend some time reading sauna owners' experiences and the same things keep coming up.
The positives are often surprisingly simple:
They relax.
They sleep better.
They enjoy the heat.
Their muscles feel better after training.
And because the sauna is at home, they actually use it.
The negatives are just as useful.
Some people complain that their sauna doesn't get hot enough.
Others mention uneven heating.
Some become frustrated by confusing specifications and claims about EMF, full spectrum or red light.
And some simply expected more.
That last point is important.
The best sauna isn't necessarily the one with the most impressive brochure.
It's the one you actually want to get into three times a week.
If you're renting, ask one more question
Renting a sauna can be a great way to find out whether you actually want one at home.
But we'd ask one question before choosing a rental company:
Why this sauna?
Not:
"What sauna do you have available?"
But:
"Why is this the right sauna for me?"
Does it suit your space?
Your goals?
The number of people using it?
The type of heat you want?
The frequency you expect to use it?
And can the company actually explain the specifications?
Because there's a difference between renting equipment and being recommended equipment.
One isn't necessarily better.
But you should know which one you're getting.
10 questions we'd ask before renting or buying
1. What type of infrared does it produce?
2. What wavelengths are being used?
3. What type of heaters are installed?
4. Where are the heaters positioned?
5. How is EMF measured, and where?
6. If it has red light, what are the wavelength and output?
7. How evenly does the cabin heat?
8. What materials and finishes are used?
9. What happens if the sauna develops a fault?
10. Most importantly, will you actually use it?
Our view
We don't think you need to buy the most expensive infrared sauna.
We don't think "full spectrum" automatically makes one sauna better than another.
We don't think a low EMF number means much without knowing how it was measured.
And we don't think sweating should automatically be marketed as detoxification.
What we do believe is that the details matter.
The heating technology.
The positioning.
The exposure.
The design.
The evidence behind the claims.
And whether the sauna actually fits into your life.
That's how we approach the saunas we rent at Recovery On Demand.
Start with the goal. Then choose the equipment.
Not the other way around.
References
[1] Beever R. Far-infrared saunas for treatment of cardiovascular risk factors: summary of published evidence. Canadian Family Physician. 2009.
[2] Laukkanen T, et al. Research on sauna bathing and cardiovascular and other health outcomes.
[3] Tei C, et al. Research into Waon therapy and cardiovascular function.
[4] Baker LB. Physiology of sweat gland function: The roles of sweating and sweat composition in human health. Temperature. 2019.
[5] Kuan WH, Chen YL, Liu CL. Excretion of Ni, Pb, Cu, As, and Hg in sweat under two sweating conditions. International Journal of Environmental Research and Public Health. 2022.
[6] Hamblin MR. Research on photobiomodulation and mechanisms of red/near-infrared light therapy.
