Studies have consistently shown that merely changing our facial expressions can change our mood. When forced to smile, people become happier, and when told to clench their teeth, they get angry. These results hold true even when participants are tricked into maintaining these facial expressions, such as when asked to clench a pencil between their teeth in a certain way. Emotions flow both ways between body and mind: just as we smile when we’re happy, we’re happy when we smile.

So the next time you’re feeling down or upset, try forcing a smile and continue smiling for as long as you can. You might just notice some of the irritation melt away.