As a society, we don't pay much attention to nutrition information when we eat out.
A U.S. Department of Agriculture report estimates just 8 percent of Americans use nutritional information when deciding what to order.
But that could change soon.
As we've reported, the Affordable Care Act will require chain restaurants with 20 or more locations to post calorie information on menus or menu boards.
And what might make us pay attention? Well, researchers at Johns Hopkins Bloomberg School of Public Health have a theory.
Instead of just listing calories, why not also include how many miles of walking or minutes of running it would take to burn off the calories you order. This could help people put the calorie counts in context.
"People don't really understand what it means to say a typical soda has 250 calories," says Sara Bleich, an associate professor in the department of health Policy and management at Johns Hopkins.
"So, if we're going to put this information in restaurants," Bleich says, listing the miles of walking it would take to work it off "may be the more persuasive way."
Bleich and her team were interested to know how low-income tweens and teenagers would respond to this kind of messaging. So she and her colleagues posted calorie and "miles to walk" signs in corner stores in predominantly black neighborhoods in Baltimore.
Since sodas are a common purchase among teens, the signs focused on beverages, pointing out that a typical 20-ounce soda has 250 calories, which would take 5 miles of walking — or 50 minutes of running — for a 110-pound adolescent to burn off. (It would take a little less time for an adult with a higher body weight to use up the energy in one of those sodas.)
"We sat in these stores for hours and watched what kids were doing," Bleich says. And her team documented that among the roughly 35 percent of teens who noticed the signs, the calorie and walking information shaped their choices.
Before the miles-of-walking signs went up, the teens were purchasing about 203 calories' worth of sugary drinks. After the signs were installed, the number of sugary drink calories purchased dropped to 179. So not a huge drop, but a significant change.
Kids also started buying smaller-size drinks. Before the signs went up, more than half of teens were buying 16-ounce or larger servings. After the signs were installed, the purchases of large-size beverages dropped to 37 percent. The findings are published in the American Journal of Public Health.
Bleich says when she started the research project, she drove through the Baltimore neighborhoods where the study was to be carried out. These neighborhoods are "low-income, heavy drug use," Bleich says. "[There are] all sorts of social disadvantages." And she recalls thinking, "Who the heck is going to care how many calories are in the sodas that they're drinking?"
But, now that she's documented that the signs do make a difference, she says she's very encouraged.
"So to me, the message is: Among a population for whom health is probably not a primary concern, we're [seeing] a significant effect," Bleich says.
And, she says, her hunch is that if she carried out the same study among higher-income populations, "I think the effects would be even bigger."
AUDIE CORNISH, HOST:
If you're looking to make healthy choices when eating out, there will be more transparency from chain restaurants in the near future. The Food and Drug Administration is finalizing rules requiring chains with 20 or more locations to provide calorie information on menus. But in order to get people to pay attention, a new study finds you might also have to help customers make sense of those counts. Here's NPR's Allison Aubrey.
ALLISON AUBREY, BYLINE: When three guys in their 20s grab a quick lunch at Taco Bell, you can bet that their appetites are big and their budgets small.
CASEY SCALL: I'm having a deal number four. It's a beefy five-layer burrito.
AUBREY: That's Casey Scall (ph) as he holds up his 20 ounce Baja Blast soda, he says he doesn't know how many calories he's eating.
SCALL: No, I have no idea. I just get it and it tastes great. And it's cheap, so I go for it.
AUBREY: And Scow's friend, Eric Sudar (ph), says at three bucks for a whole meal, including the big drink, he probably would not skip the soda, even if there were a sign telling him how many calories it had.
ERIC SUDAR: I love it. I love drinking soda. I probably drink two or three sodas a day.
AUBREY: That's a lot of calories.
SARA BLEICH: The average American has no idea how many calories are in the foods that they consume.
AUBREY: That's researcher Sara Bleich of Johns Hopkins University. She's well aware of the challenges of getting Americans, particularly teenagers and young adults, to think differently.
BLEICH: Let's say they do know that they should take in about 2000 calories. And they're making a decision at Taco Bell, like the guys we saw last night idea and a taco has 500 calories. To do the mental math to say what percent of 500 is 2000 is not something that Americans are good at.
AUBREY: Not because they can't, they just don't bother. So what would motivate them to pay attention? Well, Bleich had a theory. If restaurants listed not only calorie counts but also told customers how many miles of walking or minutes of running it would take to burn off what they ate, maybe this would work. In order to test the theory, Bleich and her colleagues did an experiment. They posted signs in corner stores in Baltimore that told teenagers it would take, for instance, five miles of walking or 50 minutes of running to burn off a 250 calorie soda.
BLEICH: So we simply watched. We sat in these stores for hours upon hours and hours and we just watched what they were doing.
AUBREY: What they found is that when teenagers noticed the signs, many made different choices. Some opted for smaller drinks, while others chose lower calorie options.
BLEICH: So we found that very encouraging.
AUBREY: Bleich says she thinks posting miles of walking could be more effective than just posting calories alone.
BLEICH: Because if we're going to put the information in restaurants, there's got to be a better way to do it. And what this study suggests is that miles of walking may be the more persuasive way.
AUBREY: So back to the guys at Taco Bell. Would the thought of all that running deter them from buying large sodas? Casey Scall says maybe.
SCALL: It would definitely make me hesitate, for one.
AUBREY: And, researchers say, well, that's a start. Allison Aubrey, NPR News. Transcript provided by NPR, Copyright NPR.