Why We Overeat
How your brain tricks you into eating more
Odds are you’re eating more than you realize. The subconscious allure of certain foods, and the hidden influences in your environment, conspire day in and day out to sway what and how much you eat.
You can blame your brain. It’s wired to manipulate you in at least two important ways: with cues such as the size of your plate, and the effects of sugar and fat on what’s known as the pleasure center of your brain.
The Psychology of Eating
Fact is, eating is fun—especially when common foods are enhanced to tempt your taste buds. So how can you not overeat in the face of such deliciousness? Brian Wansink, PhD, director of the Cornell University Food and Brand Lab and author of the book Slim by Design: Mindless Eating Solutions for Everyday Life, says the secret is to set up your environment so the apple is easy to choose and the chips aren’t. “Willpower takes [effort] 24 hours a day, seven days a week,” he says. “It’s much easier to simply change your immediate environment … than to fight against it.” Wansink and others, through behavioral science research, have discovered these tips to help you fend off temptation.
What you see matters. A study found that people who put fruit on their kitchen counter weighed 13 pounds less, on average, than those who did not have visible fruit. And those with soda on the counter weighed 24 to 26 pounds more than those who had a soda-free counter.
Fool your brain into thinking you’re eating more. Wansink found that people ate about 45 percent more food when they used a 10-inch plate versus an 8-inch plate. Your 3 ounces of pasta on an 8-inch plate looks like a full serving. But when it’s on a 10-inch plate, it looks like an appetizer size, so you add another scoop.
Blue Plate Special
A plate’s specific color won’t cause you to overeat. It’s whether the color of your plate contrasts with the color of the food you’re eating, says Wansink. For instance, if you’re serving white rice on a white plate, you’ll eat about 30 percent more than if the plate is blue.
In a study, Wansink found that food served from the stovetop prompted people to eat 25 to 30 percent less than the same food served family style at the table. When food is piled on serving dishes on the table, it’s easy to reach for seconds. So make sure you have to get up to get more. “Even though you can go back for seconds or thirds, you say to yourself, ‘Do I really want to do that? Am I really that hungry?’ ” says Wansink.
People who ate while reading, watching TV, or playing games were apt to consume as much as 25 percent more food than if they were not distracted, according to a 2013 study published in The American Journal of Clinical Nutrition.
Dimmed dining room lights can help you avoid overeating. Wansink says this creates a calming environment that encourages you to slow down and pay attention to your food. Bright lights, meanwhile, prod you to eat faster and eat more.
All of your senses are engaged while you’re eating, including sound. Fast, loud music will prompt you to eat more food, and faster. “If you’re going to have music, have it be calming and quiet background music,” says Wansink. Soft tunes can help you slow down, relax, and pay attention to what you’re eating.
Cut calories by using tongs instead of a serving spoon. According to a 2011 study published in the journal Judgment and Decision Making, it’s harder to grab food with tongs, which means you put less on your plate. This can limit your calorie intake by up to 16 percent.
Dine with one friend, and you’ll likely consume about 35 percent more food than if you ate alone, says Wansink. Share a meal with up to seven other people, and you could devour as much as 96 percent more food. That’s because you keep pace with your companions, who may order more, eat more, and eat faster.
Your server’s appearance can influence how much you eat. If your waiter is overweight, you’re three times more likely to order dessert and alcohol than if you have an average-weight waiter. The reason? Comparing yourself to someone who is larger gives you a “license to eat,” Wansink says.
As many as 92 percent of restaurants exceeded recommended daily calories in a single meal, whether it was a fast-food chain or a local bistro, according to a study from Tufts University. “At the most-popular restaurants, the average entrée plate was about 1,500 calories, and that doesn’t include the drinks, the appetizers, the sides, or the desserts,” says Susan Roberts, PhD, a professor of nutrition and the study’s lead author.
The Pleasure Principle
There’s a reason foods such as potato chips and ice cream tempt you. “We are programmed to like sugar, fat, and salt,” says Barbara Lohse, PhD, RD, CDN, professor of health sciences and head of the Wegmans School of Health and Nutrition at Rochester Institute of Technology.
Our hunter-gatherer ancestors needed a lot of calories to survive, so our brains are hardwired to seek out high-calorie foods. That explains our cravings, says Ashley Gearhardt, PhD, assistant professor of clinical psychology at the University of Michigan. That’s not so beneficial in today’s world of sedentary jobs and fast-food joints. “Our brain is still responding as if we’re in a time of famine.”
It also doesn’t help that certain foods and flavors have been optimized by companies to hit consumers’ proverbial sweet spot. Whether it’s wasabi-coated peanuts, ranch-flavored chips, or chocolate-covered pretzels, this perfect balance of sugar, salt, and fat is called “the bliss point,” says Howard Moskowitz, PhD, founding partner and chief scientist at Mind Genomics Advisors LLC.
The term was born out of a series of taste experiments conducted by Moskowitz in 1971. He mixed various amounts of sugar with water, and as the liquid got sweeter, he asked people how much they liked the taste. “They liked it up to a certain point,” says Moskowitz.
Moskowitz has optimized a slew of well-known foods using his market-research technology. He works with food companies to create countless variations of a product, tests them with groups of people, and then runs that data through an algorithm to learn the best version of a food for specific audiences.
While taste alone won’t cause you to overeat, high-sugar snacks might. There is evidence that foods with a lot of sugar can trigger an addictive-like pattern of eating, making you more likely to binge, says Gearhardt.
Let’s say you eat a candy bar. As your blood glucose level rises, so do pleasure chemicals in your brain. When your blood glucose then falls, it makes your body crave those high-sugar treats, she says, and this starts the cycle over again. “We see a relationship between your blood glucose and the reward system in the brain,” Gearhardt says, adding that more research is needed to understand the addictive nature.
Trick Yourself Into Eating Fewer Calories
Your brain may pressure you to overeat, but you can push back. “The good news is that factors that lead us to mindlessly overeat can be reversed to help us eat less without having to think about it,” says Brian Wansink, PhD.
- Don’t put fruits and veggies in your refrigerator’s crisper drawer. Cut them up, and place them in an easy-to-see spot in your fridge so your family is more likely to grab them, says Melissa Joy Dobbins, MS, RDN, CDE, a spokeswoman for the American Association of Diabetes Educators.
- Ask your server to box up half or two-thirds of your meal before it ever touches your plate, says Susan Roberts, PhD, professor of nutrition at Tufts University and founder of the online iDiet program, which claims to retrain your brain.
- At the grocery store, walk down the healthy aisles first, says Wansink. You’re more likely to buy foods from the first three aisles in which you shop than from the rest of the store.
- Use tall, slender glasses for beverages other than water. Wansink says people pour about 30 percent more into short, wide glasses than skinny ones. Why? The tall glasses look fuller.