Emotions and habits might be contagious and spread within groups in a similar manner to diseases, research suggests. A long-term study found that emotions such as happiness and loneliness as well as habits such as smoking and overeating were often found within groups such as families or friends. For example, having an obese friend increased the likelihood of a person becoming obese by 57%. It is not known for sure why emotions and habits spread, but it might be an evolutionary response in which people mimic one another because of the need to fit into a group in order to survive.
More about contagiousness of emotions:
- Having an unhappy friend increases the chances of a person becoming unhappy by about 50%, but having a happy friend makes it less than 15% more likely that a person would become happy by being around that person.
- One study found that smelling the sweat of frightened people makes people feel fearful themselves.
- About two-thirds of people who reported failing after trying to change a negative health habit said they failed because they didn’t have support from friends and family members.