When you go into a restaurant, you probably give some thought to whether you're ordering a small, regular or large sandwich.
That makes sense.With widening waistlines across the land, many of us want to make a health-conscious choice. But are we really getting a small portion when we order a small sandwich?
Well, that depends.
University of Michigan marketing professor Aradhna Krishna has studied how labels impact how much we eat. In one experiment, she gave people cookies that were labeled either medium or large, and then measured how much they ate.
The catch? The cookies were identical in size.
What happened? You guessed it. People ate more cookies when they were labeled "medium." Rather than trust what their stomachs were telling them, in other words, people went by the label.
(Listen to the radio piece above for how the same phenomenon affects people who go clothes shopping and seek out smaller sizes.)
"Just because there's a different size label attached to the same actual quantity of food, people eat more. But also, [they] think they've not eaten as much," says Krishna.
Krishna said the psychological principle at work has big ramifications because a 32-ounce soda at McDonald's is called a large soda, but the same drink at Wendy's is called a medium. A small coffee is 10 ounces at Dunkin' Donuts and 12 ounces at Caribou Coffee. When you trust labels, you could end up eating and drinking a lot more than you thought. Check out some visuals over at fastfoodmarketing.org.
Most Americans, moreover, don't realize the "large" soda they order today is about six times as large as the same soda 60 years ago, according to the Centers for Disease Control and Prevention.
"Across the U.S., again what has happened is that food sizes have become larger over time," says Krishna. "So, that same hamburger has become bigger, the french fries have become bigger, and again this is leading to obesity."
Restaurants today can label food and drink as they please. But given the power of labels in shaping behavior, Krishna said that standardizing portion sizes across restaurants could have a bigger impact on public health than New York City's controversial recent ban on all sodas larger than 16 ounces at restaurants and other eateries.
"We're not talking about restrictions in terms of freedom in any way," she said. "All I'm saying is that sizes should be made more uniform, and that will only help the consumer because you'll know what you're getting."
Sticking labels on menus isn't the only way to influence what people eat. As we've reported before, eating off a smaller plate can cause people to overestimate the serving size they've received — and eat less. Drinking beer from a straight glass, rather than a curved one, makes people drink more slowly and better gauge how much they've had to drink.
Krishna said the phenomenon of labels' influencing consumer behavior isn't unique to food. So-called vanity sizing is rampant in the clothing industry. Marketers are relabeling large-size clothes as small to give customers the satisfaction of feeling that they still fit into small-size clothing.
"What used to be a size 8 in the 1950s has become a size 4 in the 1970s and a zero in 2006," Krishna said.
In another study, Krishna and her colleagues found that vanity sizing improved people's body image. Labels shape our experiences in both positive and negative ways.
Referring to different bust sizes among women in Asian countries and in the United States, Krishna argued that people often don't have control over their body size and shouldn't need to feel blame or shame for not conforming to society's ideals. "It's not a question of being lied to," she said. "It's a question of do you want to be lied to."
STEVE INSKEEP, HOST:
Americans are growing larger - and we're not talking about height. According to estimates from the Centers for Disease Control and Prevention, about two-thirds of all people in this country are either overweight or obese. Doctors are not the only ones responding to this change. NPR's Shankar Vedantam, who joins us regularly to talk about social science research, tells us marketers are responding as well. Hi, Shankar.
SHANKAR VEDANTAM, BYLINE: Hi, Steve.
INSKEEP: Why marketers?
VEDANTAM: Well, as Americans have grown larger, they have become increasingly dissatisfied as customers. So, you know, it used to be that a size six or a size eight would fit you and now you have to get a size 10 or 12.
INSKEEP: And now you're grumpy. You feel unhappy, you feel bad about yourself.
VEDANTAM: Exactly. And the implications aren't just bad for your health, actually the implications are much worse. They're bad for business. And so marketers have come up with a really ingenious solution - it's actually been around for years - they have made the clothes larger but they re-label them as being smaller. And the phenomenon is called vanity sizing. I spoke with this marketing professor at the University of Michigan - her name is Aradhna Krishna - and she tells me it's gotten to a point where these tweaks to the label aren't small anymore, they're really, really dramatic.
ARADHNA KRISHNA: Because, in the U.S., there is so much obesity, there is greater need for vanity sizing. What used to be a size eight in the 1950s has become a size four in the '70s and a zero in 2006.
INSKEEP: That's not a tweak, that's a big deal. Why make such a big change?
VEDANTAM: The reason they make a big change is, of course, that it's very effective. Customers seem to be very happy with these clothes. They seem to buy them in greater quantities. The question that I had for Krishna, though, is do customers actually realize that marketers are lying to them?
KRISHNA: It's not a question of being lied to, it's a question of do you want to be lied to?
VEDANTAM: So, this is a really interesting philosophical question, Steve, which is if you want to be lied to, does this still constitute a lie?
INSKEEP: I am trying to sort this through, because if you're buying clothes that remind you that you're heavier than you want to be and it makes you feel bad, marketers are saying, well, it's going to make you less likely to buy clothes, maybe you'll spend less on the wardrobe. If you get the smaller size, suddenly the clothing makes you feel good. But you're saying that people perhaps consciously, or on some level, actually want to lie to themselves. That what this is suggesting?
VEDANTAM: I think that is exactly what this research is suggesting. And it used to be that vanity sizing was primarily for women's clothes. Increasingly now, Krishna tells me it's also for men's clothes. And, of course, it got me thinking about the clothes that I was wearing, so I asked her about it. So, you're saying that the size 36 pants that I think I'm wearing might not be size 36 pants?
KRISHNA: Unfortunately, yes. You actually might be wearing a bigger size and feeling that you're actually a size 36.
INSKEEP: But you're feeling good about yourself right now, aren't you, Shankar? That's important.
VEDANTAM: I am. And in fact, I think that actually my size is probably 28 and my pants were mislabeled as a 36. And it's actually gotten so out of hand because vanity preferences differ across countries. And apparently now, if you're buying women's bras, a bra that might be a size B might get labeled as a size C in some part of Asia. The very same bra could get labeled as a double A in the United States.
INSKEEP: Now, let's figure that out for a moment. People are pretending to wear smaller clothes - or let's put it another way: they're wearing clothes that are labeled differently even though they are larger. Could that actually be bad for people's health, because they're lulling themselves into thinking that they're thin?
VEDANTAM: I think there are some really important health implications here. I think you're exactly right. In fact, Krishna has done a lot of work looking at food labeling as well. So, for example, she conducted an experiment where she had identical cookies, but she labeled some of them as medium size and some of them as large size. And what she found is that people were willing to eat many more cookies when they were labeled medium size. And so what this suggests is that one potential way to address some of the obesity problems we're having is to re-label the food so that it's larger, and that might prompt people to eat a little bit less. The problem here is that in many restaurants, portion sizes are not standardized. A large soda that you could get at McDonald's is the same size as a medium soda at Wendy's. And Krishna thinks it would actually be very helpful if you went to different restaurants and small, medium and large actually meant the same thing everywhere.
INSKEEP: So, you can have some standards. And that's the problem here in the end, isn't it? The reason that people are looking at clothing labels and looking at the labels on food is 'cause you could eat any amount of food, you could probably be reasonably comfortable at a lot of different weights, and you're looking for some kind of cue as to what's appropriate.
VEDANTAM: Exactly. I mean, psychologically I think people believe the label is actually reflecting reality. But what the labels have increasingly become is they have become a psychological phenomenon to tell people how much to eat, what they're wearing and whether to be satisfied.
INSKEEP: NPR's Shankar Vedantam with supersized knowledge. You can follow him on Twitter @HiddenBrain. You can also follow this program @MorningEdition, @NPRGreene, @NPRInskeep. Transcript provided by NPR, Copyright NPR.