Restaurant chains advertising healthful food may actually encourage overeating.
The healthy restaurant trap. I'm Bob Hirshon and this is Science Update.
Several major restaurant and fast-food chains now advertise their menus as healthier than the competition. But these claims may actually fool you into overeating there. So says Brian Wansink, director of Cornell University's Food and Brand Lab. His team studied how consumers eat in both health-conscious and indulgent restaurant chains.
One thing we find is that most people eating at a healthy restaurant would be more accurate if they doubled their best estimate of how many calories they had eaten.
In contrast, people eating in decadent restaurants guessed much closer to their meal's true calorie count. And while the healthy restaurant entrees often did have fewer calories than the competition, Wansink found that people often made up the difference by adding fattening side dishes, or extra snacks later in the day. I'm Bob Hirshon, for AAAS, the science society.
Making Sense of the Research
Although Americans are pouring more and more time, effort, and money into diet foods, diet books, and diet programs, the obesity epidemic just keeps getting worse. That's partly because there are so many contributing factors, including the growing availability of cheap and convenient high-calorie meals, the widespread use of sugars and unhealthy fats in commercial foods, ballooning portion sizes in restaurant meals and in packaged foods and beverages, the popularity of sedentary activities like Web-surfing and video games, and decreases in the amount of intense physical activity—even walking—that we need to do to get through each day.
So when a fast-food restaurant advertises that its meals have less fat and calories than the competition, it might seem like a relief. Now you can eat out AND lose weight—or at least not gain any. Right? Not so fast, according to this study. Just because one restaurant has healthier (or less unhealthy) entree choices than another doesn't mean you'll actually eat healthier when you go there.
The researchers conducted several different studies of eating behavior. Sometimes they asked people to estimate their calorie consumption after they had just eaten at a restaurant; sometimes they asked people to estimate the calories in what they planned to order. They studied popular fast-food rivals (the “healthier” Subway versus the more indulgent-seeming McDonald's) as well as restaurants with healthy-sounding names (like “California Garden”).
One of the key findings was that people tend to underestimate the calories of so-called “healthy” meals more than they do for a decadent meal. Generally, Wansink's team found that people underestimated “healthy” meals' calorie counts by 20 to 45 percent. In contrast, when asked how many calories they ate after an all-out splurge, people were usually only about 10 to 20 percent under. If they ate a small amount of unhealthy food, they were actually right on target with the number of calories.
As to why, Wansink says that health-conscious advertising seems to be a little too convincing. People believe they're eating so healthfully that they feel they can eat much more than they would at an unhealthy restaurant, or load up on sugary drinks and fattening sides, and get away with it. They also found that people who just ate lunch at a healthy-sounding restaurant were more likely to snack before dinner.
Wansink calls this the “health halo” effect: the perception that just because a restaurant has less-fattening meal choices than other restaurants, that we can eat whatever we want there and still lose weight. As a result, Wansink found that people sometimes actually eat more total calories throughout the day when they eat at a healthy-sounding restaurant than they would if they ate at a more decadent restaurant. Strict calorie counters generally avoided this pitfall, but they often still ended up eating more than they might have planned. Fortunately, he says that being aware of the “health halo” effect may help people avoid the frustration of changing their eating habits and not losing weight.
Now try and answer these questions:
- What are the key findings of Wansink's research?
- What is the “health halo” effect?
- Do you think “health halos” exist in other areas besides food? For example, what about “low-tar” or “light” cigarettes?
- If advertising “healthy” restaurants is indeed making us fatter, do you blame the advertisers or the consumers? Why?
- In what way does this study illustrate the importance of scientific reasoning—not just for the researchers, but for the people dining out?
You may want to check out the November 9, 2007, Science Update podcast to hear further information about this Science Update and the other programs for that week. This podcast's topics include: when plants heat things up, how dolphins sleep, "healthy" restaurants that aren't, army ant groupies, and more.
Wansink's webiste, Mindless Eating, contains more information about this study and others, including the famous “bottomless soup bowl” study.
The National Geographic feature Why Are We So Fat? focuses on obesity. There is an excerpt from an article discussing reasons people gain weight, along with links to photos, a map, audio, video, and more.