Smiling—Even Fake—Reduces Stress

Explanation:
The facial feedback hypothesis proposes that facial expression influences emotional experience. Smiling activates neural pathways associated with positive affect, reducing stress responses—even when the smile is deliberate rather than spontaneous (Strack et al., 1988).

Example:
Holding a pen between your teeth (forcing smile muscles) may decrease stress during a tough task.

Citation:
Strack, F., et al. (1988). Facial feedback and emotion. Journal of Personality and Social Psychology, 54(5), 768–777.