Self-control doesn’t come easily when it comes to eating junk food. While many of us typically blame ourselves for weak willpower, a new study this week indicates the food we eat may actually change our brain in a way that makes it harder for us to move on to other foods when we’ve had enough of the junk. Previous research has shown that many animals, including humans, have a built-in mechanism for balancing their food intake. When a person eats a lot of a certain type of food, their brain starts to decrease the appeal of the taste of that food. As this happens, a person tends to stop eating that food and moves on to something else, naturally balancing out their diet. But there are ways around this. Prior studies had indicated that eating a lot of rich, high-calorie foods could weaken this barrier in favor of the reward these tasty treats can provide, but no research had formally confirmed this hypothesis.