"Irrational Thinking: The Word 'Natural' Sells"

ROBERT SIEGEL, host:

Behavioral economist Dan Ariely of Duke University talks with us here on occasion about how we behave irrationally. And Dan, you say a word that illustrates our lack of reason is, natural, and how we react to the word natural.

Mr. DAN ARIELY (Behavioral Economist, Duke University): Yeah. So first of all, it's kind of interesting what is really natural. And, you know, recently there's been all kinds of the news about people who run with shoes with no soles, and people who try to go back to the environment and all kinds of things.

And this kind of made me wonder about what - what is it, why do people think that running with shoes without soles is more logical. I actually met one of those guys, and I said, what about chairs? I said, well, why do you sit on a chair, wouldn't you be better on the rock?

Because he said, you know, the cavemen ran without soles, you know, why wouldnt we do the same thing.

SIEGEL: Natural floor - natural seating is what you were proposing, yeah.

Mr. ARIELY: That's right. So we tried to look at this. We went to the hospital and we asked people to make choices between all kinds of medications. And from time to time we would write this medication, you have two statins to reduce your cholesterol, this one is natural. We describe it in the same way, we just added the word natural.

The question is what would add this word do, what - how people process this information differently, and a few interesting things happened. First of all, people don't think in general that when medication is natural it's more effective. They don't think it's more powerful. They don't think it attacks the disease in a more directed way. They don't think any of this works.

But what they do thing is that it has less side effects, particularly in the long term. And we basically think of this as the caveman theory. What people do, is we think that our body is naturally attuned to the caveman era.

SIEGEL: Mm-hmm.

Mr. ARIELY: And during that time everything was kind of moving in harmony, and the medications from that time, the natural medication, fit with everything with our body, with the main disease, but also they have no unintended consequences.

They don't think that natural is more effective. What they think is a synthetic has more side effects, particularly long-term side effects.

SIEGEL: And which we're talking about a distinction between what's natural and synthetic, which is quite often really on the bubble here. I mean, it's very hard to tell what some things are, whether natural or synthetic.

Mr. ARIELY: Very hard to tell. And, you know, I took interferons for a long time which is a medication that is natural but they don't present it as one. You can think about insulin, is it synthetic or natural? There's lots of stuff. And it's actually at the discretion of the drug manufacturer about how they want to describe it.

SIEGEL: And you think if I'm selling a drug, calling it natural is an advantage.

Mr. ARIELY: I think you will do wonders for the expectations about side effects.

SIEGEL: Okay. Dan Ariely, thank you very much for talking with us once again.

Mr. ARIELY: My pleasure.

SIEGEL: Behavioral economist Dan Ariely is the author of "The Upside of Irrationality," and he appears here from time to time to talk about our irrational behavior.