Researchers at the University of Kansas found that simply smiling through a stressful situation, even when you don’t feel happy, can reduce stress. 

The study took 169 university students and divided them into three groups.  One group was asked to use chopsticks to arrange their face into a neutral expression, one group used chopsticks to arrange their face into a standard smile and the last arranged their face into a Duchenne (or genuine smile). 

Then, with the chopsticks in place, the students were asked to work on stressful multitasking activities.

According to the findings, the students that had their faces held in a standard and Duchenne smile recorded lower heart rates and reported feeling less stressed throughout the multitasking exercise.