I'm Flora Lichtenen, and you're listening to Science Friday.

Today on the show, sorting fact from fiction on cold plunges, the hottest wellness trend.

Morning, guys, it is day 87 of taking a nice bath every single day.

Let's cold plunge together.

Woo! I can't move. I don't know if that was smart, but I just did 20 minutes.

If social media and certain influential podcast hosts are to be believed, cold plunges can do

everything from boosting your immune system to reducing inflammation,

to acting as an antidote for depression. But what does the science say about all this? Here to throw

at least a few drops of cold water on the science of plunging is Dr. Francois Hamann, who studies

human performance and cold exposure at the University of Ottawa.

Francois, welcome to Science Friday.

Thank you so much for having you.

All right, let's dive in.

Should I be plunging?

That's my burning question.

So, and it is a burning question, which is interesting, because you'll be cold.

You're not going to be burning.

But when I started studying cold,

probably 25 years ago, I was not expecting the trends that we're going to be happening now.

So if you would have asked me back then, is it a good idea to jump in ice water? My answer

would have been no. The dangers of it can be tremendous.

Really? Tell me about them.

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