A team from Yale, Cornell, and Pennsylvania University asked a group of volunteers to watch a one-hour TV show. While they watched, the study participants received tubes of stacked yellow potato chips (think Pringles). Some of the tubes contained red potato chips every seventh or tenth chip.

Turns out that once you pop, you really can’t stop—unless something jolts you out of your chewing complacency. Those who received tubes containing red chips ate about half as many chips as the rest of the study participants, says Brian Wansink, PhD, a professor of food psychology at Cornell and author of the book Mindless Eating.  How come? A mouth in motion tends to stay in motion, Wansink says. That means once you start eating, you don’t stop until your brain receives a signal that it’s time to reassess whether you’re still hungry. That’s where the red chips come in. “They create the impression of a portion,” Wansink explains. “Providing that portion, or interruption point, is enough to make a person think, Hey, do I really want more to eat? And usually the answer is no.” Is Juice Really Healthy?  Here’s how to re-create the red chip effect at home: Keep snacks in small bags. There’s a reason those 100-calorie packs are so popular. Confining your food to tight quarters provides an interruption point that stops you from grabbing a second (or fifth) helping, Wansink says. You can save money by portioning out your own 100-calorie snacks—or whatever size you’re going for—in reusable containers.  Maintain a food-free perimeter. You’re a lot more likely to reach for a snack if it’s actually within reach. Keep your food in the kitchen and away from your couch or desk, and you’ll shave about 125 calories from your daily diet—or roughly 10 pounds annually, says Wansink.   When it comes to meals…Avoid family-style. Studies show you’ll eat 19 percent less at meal time if you serve yourself from the stove instead of from dishes on the dinner table. “If it’s on the table in front of you, you’ll keep picking away at it. If you have to get up to refill, that’s an interruption point,” says Wansink.  Also see: 9 Signs Your Kitchen Is Making You Fat, Everyday Snacking Mistakes, Healthy Grab-And-Go Snacks