Of all the wacky health trends, whole-body cryotherapy may literally be the coolest. Pioneered in 1970s Japan, the controversial treatment—which involves submerging oneself in a chamber of liquid nitrogen for two to three minutes—has recently gained popularity in America for purported benefits from weight loss and cellulite reduction to pain relief, athletic recovery, and even stress reduction. In Portland, private clinics like Southwest’s Active Cryotherapy and the mobile Polar Therapeutics offer some form of cryo relief. But do those claims hold up?

“The literature is pretty mixed,” says Natasha Kassam, a naturopathic doctor with Zoom Performance. “I haven’t personally seen literature for metabolic impact, cellulite, or weight loss.” But science does support other benefits, including improved heart rate variability and decreased inflammation. Perhaps the most surprising finding involves emotional wellness: the extreme cold triggers a euphoric endorphin release, and can be used to treat anxiety and other mood disorders.

Chilling in a -220°F chamber isn’t wise for all bodies—anyone with poor circulation or cardiovascular risk factors should opt for a different treatment. But for the rest of us, Kassam says, the risks (and misery level) are low. “It’s way more enjoyable than throwing yourself into a bathtub of ice,” Kassam says, “which is typically what athletes would do.”