People who describe themselves as happy tend to have fewer health problems, a lower risk of depression, and longer lives.
Most people can increase their happiness. Research suggests that, on average, 50% of people’s general level of happiness is determined by genetics. However, 40% is under people’s control, and the remaining 10% depends on the circumstances. “This implies that even if you don’t consider yourself happy, there is a good chance you have some power to change it,” says Dr. Robert Waldinger, director of the longest-running study on happiness, the Harvard Study on Adult Development. Researchers reporting in the June 2019 Psychological Bulletin combed data from 138 studies testing more than 11,000 people worldwide on how facial expressions affect emotions. They found that smiling makes people feel happier, just as scowling makes them feel angrier, and frowning makes them feel sadder. The impact was small, but smiling can have broad appeal.