There is a wealth of research about how smiling is a potent form of non-verbal communication. Helwig et al* conducted a study in 2017 which explored the dynamic properties of a smile deemed to be successful. They found a successful smile is about “an intricate balance of mouth angle, smile extent, and dental show”. How attractive your smile is to others is about how it looks.
A different study** looked at this in more depth - exploring whether a smile makeover could change how intelligent and successful someone appears. This research found that “teeth alone can have an impact on overall attractiveness and perceptions of personality attributes. One's smile clearly plays a significant role in the perception that others have of our appearance and our personality.”
It’s not just about how your smile affects those around you - smiling actually has a big effect on you too! In an inspiring TED Talk, The Power of A Smile, Ron Gutman explains how smiling actually works to stimulate your brain. A single smile can stimulate your brain to the same level as eating 2000 bars of chocolate… or getting $28,000 in cash! You can also reduce your stress levels by smiling as it enhances hormones like cortisol, dopamine and adrenaline in your body.