Social media is awash with people claiming that regular cold dips have transformed their health and well-being. We investigate whether it is actually good for you

Health



10 March 2021

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Plunging the body into cold water stimulates the release of a cocktail of invigorating chemicals

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“IT’S like pressing Control-Alt-Delete on a computer,” says Cath Pendleton. “When I’m in the water, I’m so focused on my body, my brain switches off. It’s just me and the swim.”

Pendleton, an ice swimmer based in Merthyr Tydfil, UK, is hardier than most. In 2020, five years after discovering she didn’t mind swimming in very cold water, she became the first person to swim a mile inside the Antarctic circle. Part of her training involved sitting in a freezer in her shed.

She is far from alone in her enthusiasm for cold water, however. Thanks to media reports of the mental health benefits of a chilly dip and pool closures due to covid-19, soaring numbers are now taking to rivers, lakes and the sea – once the preserves of a handful of seriously tough year-round swimmers. An estimated 7.5 million people swim outdoors in the UK alone, with an increasing number swimming through the winter. Global figures are hard to come by, but the International Winter Swimming Association has seen a boom in registered winter swimmers around the world, even in China, Russia and Finland, where water temperatures can drop below 0°C.

But is there anything more to it than the joy of being in nature, combined with the perverse euphoria of defying the cold? According to the latest research, the answer is maybe. Recent studies have begun to turn up evidence that cold-water immersion may alleviate stress and depression and help tackle autoimmune disorders. It might even tap into a …