By Stephanie Castillo for Prevention.com

Ah, “fat” days. Those miserable days when all you want to do is wear your ratty old sweatpants, watch hours of reality TV, and nosh on comfort food you’d never admit to eating.

While that’s become a staple solution for many of us, new research in the journal Obesity shows that giving into those “fat” feelings can actually make you that way.

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.

Keep reading to find out why…

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