Everyone has to walk unfamiliar roads, see unfamiliar scenery, and hear unfamiliar songs. Then, in some unexpected moment, you'll find that the things you tried so hard to forget have truly been forgotten. People who smile often have good luck. Are you a person who smiles often? Did you smile today? BuzzFeed, an American news aggregator website, reveals the secrets behind smiles and shows you how powerful a smile can be.
1. A smile makes you more at ease in the face of adversity.
A study from the University of Kansas suggests that "accepting adversity" can be a good way to cope with difficulties. The study found that when people put their hands in ice water, those who smiled remained calmer. Their heart rates were also lower during the experiment compared to those who didn't smile at all.
II. A smile makes your marital relationship more harmonious.
A study from Indiana Deutsche University shows that people who laugh more as children have happier marriages later in life. This is because positive influences from environmental and personal factors in life, such as handling interpersonal relationships appropriately, a harmonious family atmosphere, good health, and a positive and optimistic attitude towards life, can have a lasting impact.

Third, a smile can prolong your life.
A study published in the journal Psychological Science suggests that players on Major League Baseball teams who smile more tend to live longer, which is also related to a number of positive factors.
4. A smile makes you appear more trustworthy.
A study analyzing people's first impressions of others concluded that people make judgments within 100 milliseconds by observing facial expressions, and are more inclined to trust those who smile. Conversely, they feel that people who do not smile are not trustworthy.
5. A smile makes you look more friendly.
A study in Brazil suggests that college students perceive people who are always smiling as more amiable and friendly than those who are rarely seen smiling.
VI. A smile makes you more charming
This Brazilian study also shows that smiles make people look more attractive and charming.
7. A smile can be contagious.
A Swedish study showed that smiles are contagious and can make those around you smile too. When someone smiles at you, you're more likely to return the smile with a big one.
8. A smile makes things more interesting.
During the study, researchers had some participants bite down on a pencil while watching cartoons to force them to laugh. They found that those who bit down on the pencil found the cartoons more entertaining than those who didn't.
9. A smile can convey happiness.
A study published in the journal *neuropsychologia* found that a charming smile can convey happiness and increase people's perceived happiness level.