When you yawn, someone next to you will highly likely yawn. But did you know that smile is also contagious? Be happy and other people around you will tend to be happy. Surround yourself with a jolly batch and you will find yourself smiling.

Researchers from Harvard and other universities studied how social networks affect someone’s happiness. The study concluded that happiness behaves like a virus and spreads from one person to another even without direct contact.

Five thousand subjects participated in the survey together with their 50000 connections of family, officemates, friends, and other acquaintances. The proponents asked these people about subjective perception of happiness for the last two decades.

The British Medical Journal cites in a study that the happiness of one person is affected by others around him. One can be happy towards a person and that person’s might spread to his uncle, auntie, and other people. Unhappiness on the other hand does not spread as fast.

According to the new study, the key to being happy is being near with friends who are happy. It also shows that the effect of happiness on others decay with distance. You are 42% most likely to be happy if your friend lives less than a mile from you. A distance of more than 2 miles decreases the chances to 22%. Smiling is great, and it takes away the need for quite a few types of psychological health care help.

Influencing someone is a lot easier. If you are happy, they will be happy. Happiness is known to decrease the chances of heart problems, pain, and even the mortality rate.

Smile.