What Are Food Labels You Can Trust? Sorting Helpful Claims from Ridiculous Ones on Nutrition Facts Panels & Packages
You'll never read a food label or nutrition facts label the same way after you learn what food labels really mean
The Power of Packaging
Jonathon Schuldt, Ph.D., runs a lab out of Cornell’s Department of Communication. A few years ago, Schuldt, an assistant professor who studies health claims and food labeling, noticed the increasing number of health-related labels, like calorie labels, on the front of food packages: “A lot of them are candy company products, and I thought it was interesting that the color of the calorie label was green.”
Green can mean a lot of things, thought Schuldt: natural, environmental, healthy and “go.” But not, usually, candy.
So he decided to do a study. He sat students down at PCs in his computer labs and told them a story. He said, imagine you’re waiting in the checkout lane of a grocery store, and you’re hungry. You notice a candy bar (shown on the computer screen), and on the front of the wrapper is a label showing the calorie content. Look carefully at the candy bar and answer the questions below it.
The candy bar was the same, but half the students saw calorie labels in green and half saw them in red. After studying the picture and answering the questions, students rated the healthiness of the bars. The results: overall they believed the green-labeled candy bars were healthier than the red ones, even though they had the same number of calories.
Next, Schuldt compared green labels to white ones, this time in an online survey, and also asked the subjects several questions that sussed out how health-conscious they were. Turns out, the people who reported being really health-conscious judged a candy bar to be more healthful when it bore a green label. In people who weren’t health-conscious? No effect at all. Schuldt writes that “consumers who are motivated to choose healthy foods, in particular, may be swayed by green nutrition labels.”
The phenomenon extends beyond health claims. Schuldt also found that people who care about their own health or the environment also perceive foods labeled “organic” or “fair trade” to be lower in calories. Although, of course, calories are absolutely unrelated to whether something is organic or whether workers are treated properly.
“You get a halo: healthy is good, ethical is good, so ethical must be healthy. It’s faulty logic,” says Schuldt. So, people who care about being healthy, who want to make healthy choices, are more likely to be swayed by a healthy-looking label. And the biases are not just theoretical.
Last spring, Harvard Law School’s Food Law Society sponsored a conference called the Forum on Food Labeling. Mostly it dealt with the legality of labeling and how to regulate it, but, near the end, Harvard School of Public Health researcher Christina Roberto, Ph.D., a psychologist and epidemiologist who studies public health policies to reduce obesity, riveted the crowd with a series of studies on labels and how they wheedle their way into our perceptions and change our behavior. One such study used a chocolate bar as its divining rod. The researchers recruited 51 students, divided them into three groups, gave two groups a piece of the same chocolate bar, but framed the bar in different ways: the people in group 1 ate “a new health bar containing high levels of protein, vitamins and fiber and no artificial sweeteners,” the people in group 2 ate “a chocolate bar that is very tasty and yummy with a chocolate raspberry core” and the people in group 3 were the controls, receiving no bar. Subjects filled out surveys on how the bars tasted, how healthy they were and how hungry they felt before and after the snack.
The people who ate a “healthy” bar later reported being hungrier than those who ate a “tasty” bar, and even hungrier than those in the control group who ate nothing. So the researchers took this work one step deeper. They gave 62 different subjects a quarter-slice of bread, framed as either “nutritious, low-fat and full of vitamins” or “tasty, with a thick crust and soft center.” The subjects rated how healthy their bread was, after which they left the room and the experimenter told them the study was over.
Right afterward, the experimenters put the subjects in another room for an ostensibly unrelated study, filling out a questionnaire about their study habits. There were bowls of large pretzels on the table and the researchers said they were left over from another study and the participants could grab a few while answering the questions. But, as I’m sure you can guess, the original study had never ended. The subjects snacked as they filled out the form, and after they left, the researchers counted and weighed the remaining pretzels to see how much they ate.
Turns out, subjects who got the “healthy” bread ate significantly more pretzels later on than those who ate the “tasty” bread (exactly the same bread). The only difference? The perception, the claims.
“These labels influence your perception of hunger, and that, in turn, leads to how much you’re actually eating,” Roberto said at the conference. “So this is a chain that’s really impacting consumer behavior.”
It goes still further than behavior. At the Yale Clinical Research Center in 2010, 46 people were hooked to an IV and fed a milkshake. Before they drank it, half of them saw a pastel purple and blue label with a practical font and a suggestive hourglass shape. The shake was called a “Sensi-Shake,” with “Guilt Free Satisfaction” emblazoned on the front. A front-of-pack tab showed “0% fat, 0 added sugar, and 140 calories!” The other group of participants saw a shake called “Indulgence,” with a deep-red label and the phrase “Decadence You Deserve.” No health claims were made on this one, though the Nutrition Facts panel listed 620 calories per serving and the descriptor on the front said the shake was smooth, creamy, rich and delicious.
Of course, it was the same shake and it contained 380 calories. The researchers were testing subjects’ blood for ghrelin, a hormone that is secreted from an empty stomach and travels to the brain, where it binds to receptors and makes you feel hungry and want to eat. As you eat, and the gastrointestinal tract detects nutrients, ghrelin is suppressed, which tells the brain to reduce appetite and make you feel full. But research shows the relationship is not that simple.
In people with the “indulgence” mindset, ghrelin increased steeply as they hungrily anticipated drinking the shake, and then fell precipitously after they consumed it. They craved it, and then were satisfied and full afterward.
But in people with the “sensible” mindset, ghrelin levels were completely different: fairly flat. After consumption, the participants did not feel physiologically satisfied, even though they drank the same number of calories as the indulgence group. Based on the participants’ ghrelin response, you’d think the two groups actually drank different beverages. What you think about what you’re eating may have as big an effect on your appetite as what you’re actually consuming.
“This is why we need to care a lot about these labels,” said Roberto during her talk.Next: Nutrition Puffery »