American Society For Nutrition

EB 2013: When calories equal exercise, do people eat less?

EB 2013: When calories equal exercise, do people eat less?

Excellence in Nutrition Research and Practice
Posted on 04/25/2013 at 01:49:45 PM by Student Blogger
By Sarah Gold

Calories on menus -- it hasn't had quite the public health affect that we'd hoped for. Critics of the program say it's because the number is given out of context. How does a 550 calorie (with 29g of fat and 10g saturated fat) double cheeseburger fit into someone's daily calorie needs? And whose calorie needs? A 200lb muscular man, a 120 lb trim female, or 250lb overweight man or woman? What about if you add in a fries and large soda with that? Doing math while standing in a crowded fast food line with 3 kids at your side – forget it. There are also people that think that if they chose the salad over the meatball sub, they have permission to get the chips and soda with it. It's easy to see why someone without an education in nutrition might look right past those calorie numbers.

But what if we give that calorie label a little context? That may help the cause, according to research that Ashlei James, graduate student at Texas Christian University, presented at the Nutrition Education minisymposium on Tuesday.  Ashlei and her team randomized 200 men and women ages 18-30 into three menu groups: no calorie labels, calorie labels only, and calorie labels plus minutes of walking it would take to burn off those calories.  All three menus offered the same food and beverage choices, and calories burned were based on the average 150lb person walking at 3.5miles per hour. All participants were blinded and told they were there for a study on hunger cues.

The group with the calories plus walking minutes ordered an average of 139 fewer calories than the group with no menu labels, and consumed 97 fewer calories of their meal, both of which were statistically significant. There was no significant difference in what was ordered or consumed between the other two groups or between the calories only and calories plus walking group. When asked, 90% of participants from the two groups with menu labels responded that they noticed the labels.

Interestingly, there was no difference in calories consumed after the meal among the groups suggesting that group that ate less didn't make up for it later.

Similar results were found in a web-based study that tested the same idea earlier this year. These results provide some promising data for the future of calorie labeling. Consuming just 100 fewer calories at just one meal per day can result in up to a 10-pound loss in one year.

However, it's important to note that this was a small study among young men and women, and only looked at one meal in a research setting. To learn more about the general public's response to such information, it would be interesting to see this hypothesis tested in a real life setting at a fast food or chain restaurant.