Infrared vs Traditional Sauna: An Honest Guide for New Zealand Buyers

If you're shopping for a sauna in New Zealand, you'll run into the same fork in the road pretty quickly: infrared or traditional? The marketing on both sides can be loud, and it's not always clear who's giving you the straight story.

So here's ours. We build traditional Finnish saunas, so we're not neutral — but we'll give infrared genuine credit where it's due, and by the end you'll have enough to make your own call, even if that call is infrared.

The short version

An infrared sauna warms your body directly using infrared panels, while the air around you stays relatively cool — usually around 45–60°C. A traditional Finnish sauna heats the air and a bank of stones to 80–100°C, and you can ladle water onto the stones for a burst of steam.

Both raise your core temperature, lift your heart rate, get your blood moving and bring on a proper sweat. That's the important part: the core mechanism is similar. Where they differ is intensity, experience, and — this matters — the depth of the long-term research behind each.

If you want gentle, lower heat that's easy to sit in and simple to install indoors, infrared has a real case. If you want authentic Finnish heat, the steam, and the style of sauna behind almost all the long-term health studies, that's traditional.

What each one actually is

In a traditional sauna, an electric or wood heater warms a pile of sauna stones and the surrounding air to a high temperature. You sit in that hot, dry air and warm from the outside in. Pour water over the stones and you get löyly — the wave of steam that lifts the humidity and the heat together. This is the sauna Finns have used for thousands of years, and it's what most people picture when they hear the word.

An infrared sauna works differently. Instead of heating the air, infrared emitters produce radiant heat that your skin and tissue absorb directly. The cabin air stays much cooler, but you still warm up and sweat. Because the air isn't doing the work, infrared cabins run at noticeably lower temperatures and there are no hot stones and no steam.

Neither is "fake." They're simply two different ways of getting your body hot.

Side by side

The temperature question — and why it matters

The temperature gap isn't just about comfort. It's the reason the two styles sit differently in the research.

Most of the well-known, long-term studies on sauna use and health were done with traditional Finnish saunas at 79–100°C. The standout is the Kuopio Ischaemic Heart Disease study (KIHD), which followed 2,315 middle-aged Finnish men for around two decades. Men who used a traditional sauna four to seven times a week showed markedly lower risk of dementia and Alzheimer's (around 65% lower than once-a-week users), along with lower cardiovascular mortality and lower all-cause mortality.

Two honest caveats. First, these are observational findings — they show a strong association, not absolute proof that the sauna alone caused every outcome. Second, they were measured on traditional heat, not infrared. That's precisely why temperature matters: if those particular long-term benefits are your goal, the evidence points to the higher-temperature Finnish style the research was actually built on.

Infrared research is real but younger and smaller in scale. Early studies suggest infrared sessions can support heart function, ease some chronic pain, and reduce fatigue in certain groups — and because infrared still raises your core temperature and heart rate, it plausibly shares some of the same underlying benefits. It simply doesn't yet have the decades of large-population data that traditional saunas do.

What the longevity experts say

It's not just us making this point. Two of the most-cited voices in longevity have built their sauna recommendations around exactly this kind of high, dry heat.

Dr Rhonda Patrick, the biochemist behind FoundMyFitness, did as much as anyone to bring the KIHD findings to a wider audience. Her widely shared protocol — roughly four to seven sessions a week of about 20 minutes — is drawn directly from those Finnish studies, which used traditional dry saunas at temperatures in the range of about 79–100°C.

Dr Peter Attia, the longevity physician and author of Outlive, is a useful voice precisely because he started out sceptical. He initially wrote sauna benefits off as "healthy user bias" — the idea that people who sauna a lot are simply healthier to begin with — then changed his mind after looking at the size and consistency of the effect. His protocol calls for a dry sauna capable of reaching roughly 80–93°C, aiming for around four 20-minute sessions a week.

Here's the quiet detail that matters for this whole comparison: those are temperatures a typical infrared cabin doesn't reach. When the leading longevity experts specify the heat they're after, they're describing a traditional Finnish sauna — not because infrared has no value, but because the protocols the research supports are built on higher, dry heat.

One myth worth clearing up: both styles make you sweat heavily, but the "sweat out the toxins" pitch you'll sometimes see attached to infrared is overstated. Sweat is mostly water. The genuine benefits of any sauna come from the heat stress and cardiovascular response, not from sweating out toxins.

Where infrared genuinely wins

We'll be fair here, because it's true. Infrared has real advantages for the right person.

The lower temperature makes it much easier to tolerate. If high heat feels overwhelming, if you're easing into sauna use gently, or if you simply want to sit and read for 40 minutes, infrared is more comfortable. It also tends to warm up quickly, sits happily inside a spare room, and often runs off a standard power point rather than needing a dedicated cabin. For someone who wants a low-fuss, indoor, gentle-heat option, infrared can be exactly the right choice.

One practical note if you go infrared: heat-emitter quality varies, and cheaper units have at times drawn questions about EMF levels. Reputable brands publish low-EMF figures — so if that matters to you, ask for them.

The part infrared can't replicate

If there's one thing that separates the two, it's löyly — the steam. Ladle water onto hot stones and the heat surges, the air thickens, and the whole sauna comes alive. It's the heart of a traditional session, and it simply doesn't exist in an infrared cabin, where there are no stones and the air stays cool and dry.

On a cold New Zealand winter night, stepping into 80°C and pulling that steam over you is a different order of experience from sitting under warm panels. It's more intense, more social, and for a lot of people, more genuinely restorative. That's a matter of taste rather than science — but it's the reason most people who grew up with traditional saunas never switch.

So which should you choose?

Choose infrared if your priorities are lower, gentler heat, quick warm-up, an easy indoor install, and long comfortable sits. It's a sound, accessible option.

Choose traditional if you want authentic 80–100°C Finnish heat, real steam, the social ritual, and the style of sauna behind the bulk of the long-term research. For an outdoor setup that becomes a genuine part of family life, it's hard to beat.

There's no universally right answer — only the one that fits how you'll actually use it. But for most Kiwi families we talk to, the traditional experience is the one worth building your evenings around.

Our take, and where we fit

At Pure Sweat Sauna NZ we build traditional Finnish outdoor saunas — Harvia heaters set into cabins made from 38mm thermally modified Nordic pine, designed to reach and hold authentic Finnish temperatures and to live outside through New Zealand winters. We chose to build traditional not because infrared is bad, but because we think the real Finnish thing is worth it.

We're a family business in Rotorua, and Anu grew up in Finland where the sauna was the centre of the home. If you're weighing infrared against traditional and want to talk it through honestly — even if it turns out infrared suits you better — get in touch. We pick up the phone.

Explore our outdoor sauna range at puresweatsauna.co.nz · 021 244 8261 · Nationwide delivery across New Zealand.

References

1. Laukkanen T, Kunutsor S, Kauhanen J, Laukkanen JA. Sauna bathing is inversely associated with dementia and Alzheimer's disease in middle-aged Finnish men. Age and Ageing, 2017;46(2):245–249. academic.oup.com/ageing/article/46/2/245/2654230
2. Laukkanen T, Khan H, Zaccardi F, Laukkanen JA. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA Internal Medicine, 2015;175(4):542–548. pubmed.ncbi.nlm.nih.gov/25705824
3. Dr Rhonda Patrick — FoundMyFitness, sauna research overview. foundmyfitness.com/topics/sauna
4. Dr Peter Attia — Saunas: the facts, the myths, and the how-to. peterattiamd.com/sauna-facts-myths-and-how-to

The findings above are observational: they show strong associations rather than absolute proof of cause and effect, and were measured on traditional Finnish saunas. Nothing here is medical advice.