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Sauna: what the research actually says

· 14 min read · 24 sources

Sauna: what the research actually says

The famous Finnish numbers compare sauna users against sauna users, not against people who never go. Everything we found, including the null result.

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Metabolic health · Gut · Skin, hair & nails

Guides

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What lifting does to the risk of dying, how little of it is actually required, and why grip strength predicts more than almost anything else you can measure at home.

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How one dominant side starts a chain that runs all the way up into your neck, how to work out which link comes first in you, and what to do about it.

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Rounded shoulders

Why your shoulders roll forward, why stretching your chest provably does nothing about it, and what the research says actually works.

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Metabolic health

A plate of salmon, broccoli, salad leaves, quinoa, avocado and tomato on a wooden table by a window. Beside it are a glass of water, a bowl of berries, a bottle of olive oil and half an avocado, and at the edge a dumbbell and a smartwatch.

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The five numbers that describe it, what fitness turned out to be worth against them, and the two-minute intervention with a randomised trial behind it.

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Gut & digestion

Somebody rests both hands on their belly. On the wooden table in front of them stand jars of sauerkraut, kimchi, pickles and beetroot, two bowls holding yoghurt and cabbage, and fresh garlic and ginger.

Gut

What a randomised trial found when it fed people fermented food for ten weeks, why the fibre in your food beats the bacteria in a capsule, and what to do if your gut is actually unhappy.

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