Calories vs. Minutes

If you live in the United States, there's a good chance that you've already seen calorie information listed on a restaurant menu. The state of California and both Philadelphia and New York City already require it, and many restaurants are already doing it voluntarily. If you haven't yet, don't worry: the 2010 Patient Protection and Affordable Healthcare Act requires it for all restaurants.

The idea, of course, is that putting calorie information on the menu, especially in fast food restaurants, will lead people to make better (or at least lower calorie) choices when ordering. But there are a lot of obstacles to that, not least of which is whether people care about the number of calories in their restaurant food. Another issue is knowledge: while you, dear reader, probably have a good idea of how many calories you should be eating in a day, the fact is that's pretty unusual. We have patients who don't realize that a 2,200 calorie meal is more than they should be eating in an entire day. Others have the idea that they can walk around the block a few times and burn off a good chunk of their enormous Thanksgiving Day dinner.

As you might expect, this has researchers and policy makers scratching their head. How to present calorie information on a restaurant menu in a way that will lead people to make lower-calorie choices? A group of researchers based in Chapel Hill, North Carolina designed a study to see what information might be effective in influencing fast food choices (Appetite 2013:62;173-181).

Over 800 adult men and women from the UNC Chapel Hill community (staff, faculty, and students) agreed to participate in an online survey. In the survey, the participants were asked to imagine that they were at a fast food restaurant and were ordering a meal for themselves based on a generic list of fast-food-type items (no pictures). The list included, for example, 10 different types of burgers, 6 types of sides, 6 salads and 6 different dressings, and over 30 drink options.

The participants were randomly assigned to four different menu types, all of which offered the identical items. The difference was the information presented. Next to the item name, the four types of menus included one of the following:

1. No nutrition information (just the item name);
2. Number of calories;
3. Calories and the estimated number of minutes of walking equired to burn the same number of calories;
4. Calories and the estimated number of miles of walking required to burn the same number of calories.

The researchers then compared the average number of calories chosen for a participants' meal based on which menu they were choosing from. Those who were choosing from the menu with only the names of the foods averaged a meal of 1,020 calories, while those who were choosing from the menu with names and calories chose a slightly lower number of calories at 927.

Interestingly, those who were given the number of minutes of walking chose a slightly lower number of calories: 917. Yet those who chose from the number of miles of walking chose the fewest calories of all, at 826.

As educators, we were concerned to see that when the researchers compared the menu choices of those with a normal Body Mass Index with the choices of those considered clinically overweight or obese, those with a higher Body Mass Index were far less likely to make different choices based on the presented menu information, no matter what information was presented. Further, those individuals were also less likely to be able to answer basic calorie literacy questions, like how many calories an adult would require in a day.

What this means for you

Clearly the hurdle of educating the public on the appropriate number of daily calories will not be fixed by labeling menus. The researchers in this study based their estimated number of minutes or miles of walking on an average 160-pound person walking at a rate of 30 minutes per mile (2 miles an hour). You can make use of this information for yourself by estimating the number of calories you burn performing your favorite exercise and using that mental comparison when making decisions.
First posted: January 30, 2013