Practice Smiling: Reduce Pain, Improve Mood, Think Better. We feel good when we smile especially when it is about a positive thought.

A Michigan State University business scholar carried out a new study which noted that employees in customer service who put on fake smiles all that feel worse afterwards and it often affects their performance. Workers who smile due to real positive thoughts, like a tropical vacation, often have a lift in their mood, and they work better thereby increasing their performance.

Real smiles often reach a person's eyes, unlike the fake ones. So it's good to learn how to make your smile real. The fake smile where you just smile with only your mouth doesn't reach your eyes, but the natural and real ones often cause the eyes to narrow. You can try it and see.

PsyBlog says, you focus more on your tasks, and you are more productive when you smile:
We feel much better when we smile; it allows us become more focused and allows us to think clearly. Johnson et al. (2010) tested this theory and found that participants who had real smiles were more attention focused. They were able to focus more on details than just the surface look.

Smiling also reduces pain when we are going through trying times:
When we are troubled or going through some problems, putting on a smile can help reduce some of the pain. According to Psychologists, this is called the facial feedback hypothesis. Even if we have to force ourselves to smile, it still makes us feel a bit better (this is one example of embodied cognition).