Do your math when buying food

Hadley Vandiver | Boulder Weekly

The thought of doing more math on a daily basis is a terrifying prospect for some.


Even the word “math” is enough to make some people’s palms sweat and breathing quicken.

But doing a little more math, especially in the grocery store, could save those last few calories you’ve been trying to slice off your diet.

A recent study conducted at the University of Colorado Boulder shows that the serving sizes presented on nutrition labels can be misleading, especially for those who are counting calories.

Donald Lichtenstein, professor and chair of marketing in the Leeds School of Business, helped to conduct the study and is one of its authors.

“A serving size is a half bar on some candy bars, but on other wrappers, the serving size is a full bar,” Lichtenstein says. “This obviously makes the calorie count appear to be twice as large. That would be OK if you were only going to eat half the candy bar, but you’re always going to eat the whole candy bar.”

The study’s participants said that they would feel less guilty about consuming the candy bar that appeared to have fewer calories, and would then choose to consume the candy bar that they felt less guilty about. In reality, the calorie counts for both bars were almost exactly the same.

The practice of cutting down serving size to reduce calorie count is referred to as “health framing” by the authors of the study. If a company reports the entire serving size, its products are said to have “no health frame.”

Lichtenstein says that before conduct ing the study, he thought people who were more health-conscious would be more likely to pay attention to serving sizes and know exactly what they were consuming.

“The thing is, the people who are more concerned about calories are actually the ones who are more duped by it,” Lichtenstein says. “They’re more influenced by it because they pay attention to the nutritional labels, where people who don’t care about calories don’t look at the nutritional label anyway.”

Lichtenstein and the other two authors of the study, Gina Mohr, a marketing instructor at Colorado State University, and marketing Professor Chris Janiszewski of the University of Florida, found that health framing could be found in food from all sorts of categories.

“We were able to find really interesting differences in everything from packaged soups to chocolate bars,” says Mohr.

“Our findings were pretty robust across the board.”

Mohr was also shocked to learn that health-conscious people were most affected by health framing.

“I like to consider myself a healthy person, so it made me really look at my own food decisions,” Mohr says. “I’m a huge advocate of looking at labels and trying to choose foods that have the least number of ingredients. I tend to look at that rather than calorie information, and I encourage my husband to do the same.”

The idea to study nutrition labels originated with Mohr, who was a doctoral student at CU when the study began. Before surveying participants, Mohr and Lichtenstein reviewed all U.S. Food and Drug Administration (FDA) regulations on how serving sizes are determined, and found that manufacturers are given a fairly large amount of freedom in the matter.

“There are two things going on here,” says Lichtenstein. “The FDA gives companies some leeway in deciding serving sizes, and that is enough to influence consumers. But the other thing is that lots of companies go beyond what the FDA allows, so they’re actually not even consistent with the law.”

Though such violations of FDA regulations exist, they are seldom prosecuted, a fact that Lichtenstein attributes to lack of manpower. Until there is a change in FDA regulations, he says, the responsibility rests with the consumer to thoroughly analyze nutrition labels.

“Do the math,” Lichtenstein says.

“Go into the store, and when you’re looking at calories, look at how many servings that calorie represents and what the serving size is, and do the math. Don’t just compare calories per serving to calories per serving, because this serving size may be twice the size of that one.”