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Translating Calorie Counts into Exercise Equivalents Leads to Healthier Choices

The views expressed are those of the author and are not necessarily those of Scientific American.

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By mid-2012, coffee shops and burger joints across the country will be required to prominently display nutritional information about their food products. Many of the larger franchises are already doing this. But does knowing the number of calories in a caramel latte make you more likely to choose a fat-free coffee?

Unfortunately, no—most studies have found that caloric signage has little or no impact on the food choices that customers make. But that may be because people don’t have a clear idea about what those calories mean, suggests Sara Bleich, a health policy expert at Johns Hopkins Bloomberg School of Public Health.

“When my husband eats junk food, he always says he’ll burn it off later,” Bleich says. “And I’m thinking, ‘No you won’t, honey.’ ”

The 250 calories in a bottle of soda may not sound like much, but to work off those calories, a 15-year-old weighing 110 pounds would have to jog for 50 minutes, ride a bicycle for 73 minutes, or walk briskly for two hours. Adults would have to work even harder, to compensate for their slower metabolism. In a recent study published in the American Journal of Public Health, Bleich found that translating calories into a physical activity equivalent can help customers make healthier choices.

Bleich’s team posted nutritional information on the beverage coolers of three Baltimore corner stores. In each store, the signs held one of three messages:

  • “Did you know that a bottle of soda or fruit juice has about 250 calories?”
  • “Did you know that a bottle of soda or fruit juice has about 10% of your daily calories?”
  • “Did you know that working off a bottle of soda or fruit juice takes about 50 minutes of running?”

The researchers then watched to see whether the signs had any impact on the types of drinks bought by African American teenagers, who are at higher risk for obesity than white teenagers, and who also tend to drink more sugary beverages. In the store whose signs provided the physical activity equivalents, a black teenager’s odds of buying soda or other sugary drinks was halved, as compared to before the signs were posted. The other two treatments—listing the raw calorie count or percent of daily intake—also appeared to decrease the consumption of sugary beverages, but the effects were not statistically significant.

The results are still somewhat preliminary, since the study only looked at one store for each type of sign. Future studies will determine whether the physical activity signage will have similar effects in other populations. Still, Bleich thinks that it may be time to start thinking about alternatives to plain old calorie counts.

“There is a great window of opportunity right now,” she says, because the legislation that will require fast food chains to post calorie counts does not specify exactly how that information should be presented. Of course, it would be difficult for a Starbucks to put a statement like “It takes x hours of bicycling to work off this drink” next to every beverage on its menu, but Bleich says that they could add the signage elsewhere, such as next to its baked goods. Customers could then extrapolate that information to their other menu choices.

No matter how illustrative the presentation, it will take more than a calorie count to help customers make healthy decisions at fast food restaurants. “Posting nutritional information has the greatest effect on people that are interested in making behavioral changes—people who want to lose weight or who care about nutrition,” Bleich says.

Image Credit: Flickr/ironchefbalara

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  1. 1. 1:23 pm 12/16/2011

    This makes so much sense! What’s a calorie? No clue. But an hour of jogging I can understand!

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  2. 2. svande8952 4:11 pm 12/16/2011

    I agree this is a good idea, however, calorie burn/hour varies greatly with weight and intensity of activity. A 200 pound man can burn 150 calories by running 1 mile, but some people can run that mile in 6 minutes while others will take 12 minutes. Accurate information will be important. A 110 pound 15 year old running at 7.5 mph for 50 minutes will burn much more than the 250 cal in the example.

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  3. 3. dragonasbreath 12:07 pm 12/17/2011

    also, what is my basal metabolic rate? AS in, how much will I burn vegging on the couch watching tv as my body powers the brain and the rest of the workings?
    How many calories did I just burn on the job? IF it doesn’t count there, it doesn’t count on the exercise floor either – same arguement applies – body becomes accustomed to that 10 mile jog, now you have to do 20 miles to achieve the same effect. It’s either/or folks, you can’t have it both ways.
    I just spent an hour sweeping, moping, dusting, scrubbing – how many calories did I burn? How about going up the stairs to get whatever it was I needed up there?
    These little calorie charts are worthless and will be treated as such if they don’t include ALL the data – and as svande8952 pointed out, how much you burn depends on YOUR basal metabolism, not some insurance point chart.

    As for the Latte, it’s simple really –
    the Carmel Mocha is to die for, the fat-free decaf tastes like warmed over sawdust.
    Which would you choose?
    If they TRULY want us to choose the “healthy” (changes by the week, doesn’t it?) over the “unhealthy”, then the tastes must be the same. And no, Carob DOES NOT taste like Cocoa.

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  4. 4. dragonasbreath 12:09 pm 12/17/2011

    Going back to brain – and this is actually a question: What is the difference in calories needed to run my brain if I am just enjoying what’s flowing on the screen in front of me vs reading a book (more involvement) vs doing my homework?
    The brain is doing different things, powering different portions of it’s network, logically the power usage should be different in different areas.

    And what about the research that shows if I meditate really really hard on lifting those weights, my body will respond as if I did – it’s ALL in the brain, after all.

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  5. 5. kevin_neilson 3:07 am 12/18/2011

    First of all, a soda has 250 Calories, not 250 calories. Big difference. Second, it doesn’t require 50 minutes of running to burn it off. I haven’t done any exercise in weeks, and I’m still burning almost 2000 Calories a day.

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  6. 6. leoluca criscione 1:15 pm 12/19/2011

    This ‘study’ belongs to the chapter: “Science produces and feeds the confusion”. As pointed out in the comments, the total energy (Calories)which a body burns depends from the PERSONAl Basal Metabolic Rate as well duration and intensity of a given activity…. etc etc Please read more following the article connected with the following LINK…

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  7. 7. sunnystrobe 6:21 am 12/21/2011

    Years of nutritional studies have shown me that human nutrition is out of kilter for one main reason:
    Our obsessional tinkering with our food! Every time we cook we artificially dehydrate, and thereby, condensate all the ingredients! The result is: 10times, 50 times, 100times more calories per bite than before.
    We are killing ourselves with condensates, because our body organs, being humble primate designs, are not geared for this, our pancreas cannot cope with hundreds of kilos of sugar per year: that’s diabetes for you; our kidneys get pickled from salty food like gherkins: that’s high blood pressure now, kidney failure later..
    Our livers get artificially fattened from ham, salami, cheese, looking more like goose liver pate, from feeding on artificially fattened animal carcasses, oils, mayonnaises, plus ethanol from beers,wines, spirits:
    that’s a recipe for hepatitis & cancer risk for the future.
    Calories are far too abstract to be taken on board; let’s opt for COLORIES instead!
    From raw fruits and vegetables, which store their anti-oxidant energy in their peels and tissues, as we now know. I lost more than 20 kilos just by eating a big apple before meals, and salads as hors d’ hoeuvres!
    This leaves little room for any condensates.
    Visit Youngevity. com for more specific explanations
    about the Colorific Diet principle.

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