From APM, American Public Media, and WNYC.

This is Freakonomics Radio on Marketplace.

Here's the host of Marketplace, Hiras Doll.

Time now for a little bit of Freakonomics Radio that moment in the broadcast every couple of weeks

where we talk to Steven Dumbner, the co-author of the books and the blog of the same name.

It is the hidden side of everything. And Dumbner, you know what?

I'm especially glad to have you back this week, you know what?

I know why.

You do, I know, you send me something. I love it when you send me things.

I send you something. What can I tell you? I'm a benevolent kind of fella.

That's right. So go ahead, Kyle. Open up your little pack.

Alright, here we go.

Alright, it's a little bubble wrap envelope with an envelope inside.

Very careful. Very careful.

Okay, so it's back of Mar-Bos. Mar-Bos.

And I don't smoke, dude.

Believe it or not, I'm trying to help you stay trim.

Alright, so I want you to listen to Kip Viscousey, who's an economist at Vanderbilt,

who studies smoking.

Alright, well one thing is that if you give up smoking, you'll gain some weight.

It may not be enough to make you morbidly obese, but it'll make you a little heavier.

Alright, so here's the hidden side, right? It's the unintended consequences of giving up.

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