Before you take another sip: How many calories in a 20-ounce soda? And do you know how many miles you have to walk to counteract those empty, sugary calories? You might be unhappily surprised.
Teens guzzle more soda than any other age group — but when they know just how hard it is to work off those liquid calories, even they are more likely to pick a lower-calorie drink, a new study shows.
“Americans don’t know about the number of calories they need in a day,” says Sara Bleich, an author of the paper and professor of health policy and management at Johns Hopkins Bloomberg School of Public Health.
In the study, published Thursday in the American Journal of Public Health, Johns Hopkins researchers posted one of four signs with easy-to-understand nutritional information at six different corner stores in African-American neighborhoods in Baltimore.
One sign displayed the absolute calorie count of a bottle of 20-ounce soda, an estimated 250 calories.
Another sign asked: “Did you know that a bottle of soda or fruit juice has about 16 teaspoons of sugar?”
A third claimed: “Did you know that working off a bottle of soda or fruit juice takes about 50 minutes of running?”
And the last sign said: “Did you know that working off a bottle of soda or fruit juice takes about 5 miles of walking?”
When teens saw any of the four signs, they were more likely to choose a drink with fewer calories.
But the signs that informed them how much exercise they had to do to burn off their drink encouraged more people to purchase lower calorie choices.
“We were pleasantly surprised,” says Bleich.
Knowing that it takes about 10,000 steps — the equivalent of walking 5 miles — to burn 250 calories, that 20-ounce soda, would probably be even more effective with adults.
“I think you would see a larger effect in … adults because they care a little more about health," says Bleich.
And if you drink more than one big soda, that's 500 calories. To burn that off, you'd have to do 600 push ups, an hour of jumping jacks or 75 minutes of hula hooping, according to TODAY's lifestyle and fitness correspondent Jenna Wolfe.
When the Johns Hopkins researchers asked the teens later about their habits, they still purchased lower-calorie drinks, based on what they'd learned.
“We again observed [that] the behaviors are persistent,” she says. “It is very encouraging.”