This document outlines 10 reasons to smile, including that smiling makes us more attractive to others, can positively change our mood, is contagious, relieves stress, boosts the immune system, lowers blood pressure, releases endorphins and serotonin that make us feel good, lifts the face and makes us look younger, makes us seem more successful, and helps us stay positive. Smiling provides both physical and psychological benefits such as reducing stress, improving mood, and making us more approachable.