From the Vancouver Sun, by Amy Husser

[…] A team of U.S. researchers has discovered that imagining the process of eating a desirable food — bite by bite — actually curbs your craving to chow down on it.

“Thinking about something desirable increases its desirableness,” says Joachim Vosgerau, of Carnegie Mellon University in Pittsburgh. “The counter-intuitive thing that we show is that it can also have exactly the opposite effect — it can decrease the desire for something.”

Dream diet to eat less and lose weight

Dream diet to eat less and lose weight

Vosgerau says there’s “all sorts” of research showing that imagination and experience are quite similar. In fact, he says, the same regions in the brain are activated whether someone is experiencing or imagining a stimulus.

“If imagination and experience are so close together, then imagining the eating of food should have the same behaviour consequences as actually eating it. That was the idea from which we started.”

In order to prove their theory, the CMU researchers completed a series of experiments, each using between 50 and 80 people.

In the first, three groups of participants visualized performing 33 repetitive tasks, one at a time. The control group imagined loading 33 quarters into a washing machine; a second group imagined putting in 30 quarters, then eating three M&Ms; and the final group imagined loading three quarters and eating 30 M&Ms.

Following the exercise, participants were placed in an environment where they could freely eat from a bowl of M&Ms. Those in the group who had thought about eating the larger amount of candy ate “significantly fewer” of the M&Ms — in fact, nearly half the amount of the other two groups.

Vosgerau attributes the finding to a “habituation” process — or a gradual reduction in motivation to perform a function as your body becomes accustomed to it. For example, the researchers note, the first bite of chocolate bar is often much more satisfying than the last. Or there’s an adjustment period after you take off your sunglasses in bright daylight.

“When you simply think about the stimulus — such as a steak — then it increases its attractiveness. But when you think of the repeated consumption of the stimulus, then you get exactly the same behaviour consequence as if you were eating it,” Vosgerau says. “That decreases its attractiveness.”

Another series of tests found that imagining snacking on a specific food was key; merely thinking about a delicious dish or visualize eating another treat did not significantly influence consumption later. […]

More on http://www.vancouversun.com/Dream+diets+food+thought/3955987/story.html

Joachim Vosgerau also gave an interview to ABC Australia:

MARK COLVIN: There’s new evidence today of the power of imagination. US researchers have shown that people can cut their desire to eat certain foods if they repeatedly go through the motions of devouring them in their mind’s eye. There’s potential in the findings to help break food addictions and even to help people quit smoking.

Ashley Hall reports.

ASHLEY HALL: The researchers started out with a simple premise; that a person’s imagination and actual experiences manifest themselves in a similar way.

JOACHIM VOSGERAU: Imagine a spider crawling over your leg, yeah? Has the same behavioural consequences than if the spider actually crawls over your leg.

ASHLEY HALL: They wondered, could that premise be extended to thoughts about food?

Joachim Vosgerau is a professor of marketing at Carnegie Mellon University in Pittsburgh, and one of the authors of the study, published in Science magazine.

JOACHIM VOSGERAU: I thought that was actually a crazy idea. I didn’t believe that this would work but I like crazy ideas so we said, let’s see whether that’s true and we designed and experiment and was totally stunned when we got the results.

ASHLEY HALL: The researchers tested their theory by dividing the participants into groups and asking each group to imagine eating a different amount of chocolate. Then, they gave them a big bowl of chocolate and told them to eat as much as they could.

JOACHIM VOSGERAU: So it turns out that the group that imagined eating more MandMs, they ate less MandMs than the other two groups.

ASHLEY HALL: So they imagined themselves to a state of fullness?

JOACHIM VOSGERAU: That is actually the one potential explanation: that simply by imagining eating all those MandMs you get this sensation of feeling of being full, yeah? But then we did another experiment to test that.

ASHLEY HALL: They asked people to imagine eating chocolate or cheese, with the researchers offering them a big bowl of cheese afterwards. Those who’d imagined eating cheese ate far less of it than those who’d imagined eating chocolate.

JOACHIM VOSGERAU: It is specific to the food that you imagine eating that brings about the success.

ASHLEY HALL: So do we know what is at work there? What’s going on in the brain?

JOACHIM VOSGERAU: Yeah, we believe the effect or the mechanism is habituation. So habituation is a gradual decrease in the motivation to obtain that food and habituation is food specific.

So it’s like in real life when you eat, for example, a steak, with each bite of the steak, the steak becomes less desirable and your motivation to eat more of the steak declines. But then that has not much of impact on your desire for eating let’s say ice-cream for dessert, yeah? So it is a food specific effect.

ASHLEY HALL: It might explain why children who say they simply can’t eat another mouthful of their dinner still have room for dessert. Joachim Vosgerau says a similar but different principle is used in advertising.

JOACHIM VOSGERAU: There’s a lot of research that shows if you just think about a stimulus, only once, then it increases in its attractiveness. So if you just think about the steak, then your desire to eat the steak increases.

So you get this effect of habituation with a decrease in the desire to eat the steak only if you repeatedly think about it and so this is the difference between what we are doing and what is done in advertising. In advertising you are typically only motivated to think about the stimulus and it’s only once, not repeated, like 30 times or so.

ASHLEY HALL: So are there applications for the findings of this study in day to day life? Particularly, I imagine, in the field of weight-loss?

JOACHIM VOSGERAU: You have to be careful. You have to keep in mind that this is a food specific effect. So it’s probably not, it’s not going to work in terms of curbing your hunger or so. But what you can use it for is to substitute foods.

So if you’re tempted, for example, by chocolate brownies, then thinking intensely about how you eat chocolate brownies bite by bite will decrease the desire to eat chocolate brownies and therefore you can probably eat something else. But it will not work in terms of decreasing your overall hunger level.

ASHLEY HALL: The researchers believe their findings might also help people wanting to quit smoking.

JOACHIM VOSGERAU: When you’re a smoker and you’re trying to quit smoking the most difficult problem is that you have those recurring thoughts about smoking. So typically you try to suppress the thoughts which is very effortful and very painful and according to our theory one should do exactly the opposite.

So whenever the craving comes and you think about cigarettes, you should engage in thinking as vividly as possible smoking a cigarette drag by drag. And that will actually decrease the craving.

ASHLEY HALL: It’s a technique Joachim Vosgerau has himself adopted to quit cigarettes. So far, he’s managed two weeks.

MARK COLVIN: Ashley Hall. And I don’t know about you but parts of that story actually made me feel hungry.

From http://www.abc.net.au/pm/content/2010/s3090570.htm