Bake Your Body, Boost Your Brain?

Wellness gurus have been bullish on the mind-enhancing benefits of saunas. But how much of it is just hot air?

- By Carolyn Todd

From the Huberman Lab podcast to your biohacker buddy's garage to your social feeds, saunas are everywhere right now. Part of the surge in interest (and sales) is largely thanks to science showing a connection between frequent sauna use and better mental and physical health and maybe even longevity-including some stunning evidence that it may help prevent dementia. Not to mention the whole sauna thing: the community, the relaxation, the ritual, the ahh moment.

Most of the research on brain benefits comes from Finland, where sauna bathing is a pillar in the culture of being healthy and happy. The sauna is the poor man's pharmacy, goes one old proverb. And increasingly, science agrees.

A few years ago, when Finnish researchers dug into some overlooked data on chronic disease risk-numbers they'd been collecting on middle-aged men since the 1980s-they noticed a startling link, says Jussi Kauhanen, M.D., Ph.D., director of public health at the University of Eastern Finland and head of the research group today.

Scientists in any other country wouldn't have thought to include "How often do you sauna bathe?" on the lifestyle questionnaire. But in Finland, where it's essentially as universal as diet and exercise, the question seemed only natural, Dr. Kauhanen explains.