Sylvia Jeffreys tried a radical health treatment and we can't look away.

Cryotherapy is the latest craze in celebrity-land but in the real world, it’s been around for hundreds of years. And this week, Today show host Sylvia Jeffreys agreed to give it a go.

Cryotherapy is meant to help with pain and weight loss, as well as help heal injuries and promote better sleep. Being the good sport that she is, Jeffreys agreed to “freeze her backside off” to try and figure out if it’s all it claims to be.

Famous U.S. athletes are fans of the method including basketball player LeBron James as well as Real Housewives star Yolanda Hadid. This is Us star Mandy Moore has also tried it.

Cyrotherapy is the latest celebrity craze. Image: Today Show, Nine Network

Jeffreys was put in a cryotherapy chamber at minus 130 degrees. Yikes. Immediately Jeffreys felt a cold blast go into the machine and with fingers and toes protected by gloves and ugg boots, the rest of Sylvia was left to freeze. Soon she said it was "stinging".

Cryotherapy works using liquid nitrogen that blasts the body, causing it to go into survival mode which sends your blood to your heart. After three minutes you step out and that freshly oxygenated blood gets pumped through your body with its magical healing powers.

Jeffreys said the therapy has been around for a long time. "Cold therapy was used back in ancient Greece. The Japanese the modernised it in 1978." And now, it's back.

Sylvia Jeffreys tries out cryotherapy treatment, says she didn't notice any weight loss. Image: Today, Nine Network

"It's an interesting experience," Jeffreys told her Today colleagues. "I made it through six sessions and got to three minutes by the end of it so you have to work up to it."

"Would I keep doing it? I'm not sure. It's about $90 a session on average depending on where you go and how many you purchase. But I can see how it works for injuries and for top athletes."

When it comes to whether or not the therapy lives us to its claims when it comes to weight loss, Jeffreys was skeptical.

"You have no weight to lose whatsoever," Lisa Wilkinson told Jeffreys, "but was there any weight loss?"

Jeffreys says no, that she wouldn't attribute weight loss to the therapy but rather healed injuries, pain relief and increased energy which makes it easier to exercise.

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