Imagine perusing the menu at a restaurant. You’re feeling virtuous so you skip the burger and fries and order a healthy green salad. An hour later, you’re feeling ravenous, even though the salad was quite large. What happened?

You’re not alone. A new study shows that eating food described as healthy may actually make people hungrier afterward than if they ate the same thing described as tasty.

To test this theory, researchers asked fifty-one college students to try a chocolate-raspberry protein bar. Half the students were told they were sampling a new health bar, which was chock full of vitamins and fiber. The other half were told they were getting a yummy chocolate bar with a raspberry center.

When asked to rate their hunger later, those who ate the healthy bar reported feeling much hungrier than those who had the yummy bar. In fact, those who ate the health bar said they were hungrier than those in a control group who ate nothing at all!

Why is this finding important? It might help unlock the reason so many dieters experience frustration while trying to peel off the pounds. While they might feel good about themselves for picking healthier options at meals, many go home and binge on a decadent dessert later because they are still feeling the need to nosh.

Understanding this phenomenon is the first step toward reversing this trend, scientists hope. So the next time you feel like reaching for a slice of carrot cake after downing a snack of carrot sticks, stop to think before you indulge.