Norwegian researchers tracked adolescents into adulthood to see how their weight perceptions influenced their actual weight later in life. And the findings weren’t good. Adolescents who were normal weight—but who perceived themselves as overweight—had a larger weight gain by age 30 than teens who perceived their weight as normal. In other words, feeling “fat” turned out to be a self-fulfilling prophecy. These new findings build on earlier research from the University College London showing that the brain appears to create a map of your body based on different cues—including the messages you tell yourself about your weight. That means that if you spend your days saying unkind things to yourself about your body, it’s going to give you the wrong idea of what it actually looks like. So if you want to stop feeling “fat,” you have to start thinking thin. And if you don’t know how to do that, we’ve got you covered. Check out 10 Ways To Turn Around A “Fat” Day.