RENEE MONTAGNE, host:
Here's a new dieting strategy for the holiday season: virtual eating. Scientists staged a test to find out whether you eat more ore less if you spend a few minutes imagining eating before you take your first bite.
NPR's Allison Aubrey tells us what they found.
ALLISON AUBREY: Nothing about the experiment I'm about to describe to you may seem applicable to the way we eat in the real world. But stay with me. The researcher who led the study is Carey Morewedge, an assistant professor at Carnegie Mellon University. He and his colleagues bought pounds and pounds of M&M's and recruited a few hundred volunteers to take part in a short imagination exercise. As volunteers entered their lab, they were seated in cubicles in front of computer screens.
Professor CAREY MOREWEDGE (Carnegie Mellon University): So on the screen, you'd see a photograph of white bowl containing M&M's.
AUBREY: Some volunteers were told to imagine themselves picking up the M&M's and moving them one-by-one into a container. Others were instructed to actually envision consuming the candy, putting the chocolate in their mouths.
Prof. MOREWEDGE: Yeah, every three seconds you would see a different M&M, and it would say please imagine eating this M&M.
AUBREY: After volunteers finished imagining, either just moving the candy or eating it, they'd raise their hands and the researchers would bring each of them a bowl of real M&M's. They were all told to eat as many as they liked. But as it turned out, the candy movers ate a lot more, nearly twice as much as the other group. David Just of Cornell's Center for Behavioral Economics in Child Nutrition has one explanation.
Professor DAVID JUST (Center for Behavioral Economics in Child Nutrition, Cornell University): If you sit there and think about M&Ms - and for them, it was just thinking of taking M&Ms and putting them in a bowl - you're going to eat more of them, because you're thinking about them more and it primes you for this experience. It makes you want them more.
AUBREY: Just says in sharp contrast, the volunteers who'd spent all their mental energy picturing themselves actually eating the candy seemed to want less of it. It's as if their brains confused the mere act of imagining eating with real consumption.
Prof. JUST: If you start imagining yourself eating the M&M's, your body's actually going to produce some of the dopamine and some of the, you know, physical response to having eaten. So when you see the M&M's, it's not as new. It's sort of old hat, and you don't eat as much.
AUBREY: So is the take home message here that we all might be able to cut calories by taking up this practice of, well, virtual eating, imagining what we consume before we put it in our mouths?
Dr. SUZANNE HIGGS (University of Birmingham): I think it would be stretching things a little, but nevertheless, I suppose we would want to know, you know, whether or not this kind of strategy would work for people in their ordinary lives.
AUBREY: Researcher Suzanne Higgs of the University of Birmingham says this new study, published in the journal Science, makes a nice contribution to what's become a very hot research topic, untangling all the ways that our thinking processes influence our eating habits. Her own studies focus on distraction. And she's shown that if people are not paying attention when they eat a meal, say if they just munch away on auto pilot as they watch TV, they tend to over-consume.
Dr. HIGGS: Well, when people are distracted from their lunch, we find that given the opportunity later in the day to eat consume cookies, they actually eat more cookies than if they weren't distracted when they ate their lunch.
AUBREY: Higgs says her research and the new imagination studies both show that feelings of hunger and satiety are not just determined by how full our stomachs are. Our minds play an important role, too.
Dr. HIGGS: At first glance, perhaps the results do seem a little bit counterintuitive.
AUBREY: But she says if you think about it, it makes some sense. People are more likely to notice the sensation of feeling full if they've put a little mental energy into thinking about what they're eating.
Allison Aubrey, NPR News.
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