The least-hard hard thing you can do for your health

Friday, 19 June 2026

'Can you tell us about saunas and the health benefits? I think more people should know about these!'

Is a sauna actually as good for you as everyone says?

The sauna is an ancient ritual that’s made a modern comeback with the wellness movement. But unlike some ‘health hacks’, there is solid science to back sauna up. Let’s talk about it.

What does the research actually show?

Finnish researcher Jari Laukkanen tracked 2,315 middle-aged men for over two decades in the Kuopio Heart Disease Study. The men who sauna'd more than four times a week, compared to once a week, had a 63% lower risk of sudden cardiac death, a 50% lower risk of fatal heart disease, and a 66% lower risk of dementia and Alzheimer's. Over 20 years the sauna users had a 40% less chance of dying of anything.

Sitting in a hot room is one of the most powerful non-drug things you can do for your heart, your brain, and staying alive healthy. Just by sitting in a hot box. It's not that hard. Maybe it's the least-hard hard thing you can do for your health. It's good for us precisely because it is hard.

Why does it work?

The traditional Finnish sauna, 80 to 100°C, 15 to 30 minutes, is the one with the evidence. That heat is a stress, but a manageable one. The biological name for this is hormesis: a dose of stress that pushes you enough but not too much, so you activate your repair systems. You build a better version of yourself because of the stress. Heat shock proteins are produced and help protect every cell in the body, including in the brain. Your brain releases dynorphin, which feels slightly unpleasant in the moment then tunes up your mood afterwards.

What about infrared?

You may have also heard about ‘infrared’ saunas? Are they different and do they still work? Well infrared runs much cooler at 45 to 60°C, and uses light rather than ambient heat. The light is absorbed into the energy heart of every cell, your mitochondria, and literally helps move electrons in the part that produces energy. While the actual health research is much more limited than the Finnish sauna, it's certainly plausible that something helpful is going on. Early trials shining near-infrared light straight at the head show benefits for cognition in mild Alzheimer's. This was a targeted device rather than a sauna, and the evidence is still preliminary.

For fitness?

A sauna after exercise can extend your adaptation without any extra movement. The heat triggers similar changes to altitude training, increasing your blood's capacity to carry oxygen. In one study, three weeks of post-exercise sauna sessions improved endurance by over 30%. It also helps muscles recover faster, which matters more than most people realise for staying consistent.

One practical note: replace your fluids and electrolytes afterwards. You can lose around a gram of sodium in a single session, which matters more than most people realise.

How to do it

Get hot enough that at some point you feel that surge of dynorphin, the chemical trigger that tells your brain, 'I've had enough, I’ve got to get out of here. I'd say 80°C or more, for up to 30 minutes. I usually do three rounds of 10 minutes with some outside cooling in between to break the stress.

Who should be careful?

Pregnant women, and anyone with severe uncontrolled high blood pressure (above 180/110), a recent heart attack, or severe heart failure, until they've checked with their doctor. And sweating out a cold or flu is a myth, don’t do that.

No sauna? No problem.

A hot bath does a lot of the same work. Obviously you can't jump into 60°C water, you'd die. But a bath as hot as you can bear, or a spa pool at 40°C, gives a decent heat stress too. Water moves heat into your body far more effectively than air, so your bathtub and spa are useful tools.

Me?

I saved up and put a sauna in at home, and honestly it's one of the best things I've bought, expensive as it was. Louise and I use it a few times a week, and my boys all use it. Better still, it's the one place in the house that's device free, where they actually sit and talk to you. I've really noticed my sleep improving on sauna evenings.