Want to Eat Less Junk Food? This Science-Backed Trick Works Every Time

Updated: Jan. 23, 2017

When facing a yummy, unhealthy treat, whether it's cheesecake or cheese fries, new research sheds light on an easy way to eat less of it.


Many people struggle with portion control. But even if you can’t tell a golf ball from a deck of cards when it comes to rice, beans, or a burger, researchers have found another way you can control your portions, especially when eating guilty pleasures like pasta and dessert. The trick: Serve yourself.

You know the struggle well if you’ve ever eaten at a restaurant and managed to plow through the obscene amount of food that appeared on your plate. According to new findings from the USC Marshall School of Business, not serving your own food makes it easier to deny responsibility for how much makes it into your mouth. “Our research shows that for unhealthy—but not for healthy—food, consumers are more likely to indulge and have larger portions when they are less involved in serving the food, like when another person serves it for them or when it’s already pre-plated,” says study co-author Linda Hagen, assistant professor of marketing at the Marshall School of Business at the University of Southern California. “They’re less likely to indulge and will choose smaller portions when they have to serve themselves.”

[pullquote] When participants served their own unhealthy foods, they were more likely to either skip them altogether or take skimpy portions. [/pullquote]

In Hagen’s research, which will be published in the Journal of Marketing Research later this year, the team found that when participants served their own unhealthy foods, they were more likely to either skip them altogether or take skimpy portions compared to when they grabbed pre-filled cups, pre-sliced cake, or pre-set sizes of frozen yogurt. “When people are more physically involved in serving their food, they feel more responsible for their eating choices and are more likely to curb their unhealthy eating to avoid feel guilty,” says Hagen. “In other words, serving your own food can be a tool to help hold yourself more accountable.”

If a healthy weight is your goal, cut back your unhealthy eating at home by always filling your own plate rather than letting a relative plate your meal, never eat out of big bags of chips or crackers or cookies (because you can’t see how much you’re munching), and always plate your take-out instead of chowing it straight from the container. At parties, ask to slice your own cake instead of taking a piece pre-cut by the host.

These findings might have implications beyond just the average person eating at home. For example, it could potentially help kids make healthier choices at a school cafeteria.