Happiness is like a disease, an infectious disease that is catching. Every time you smile at someone, you spread joy. And, if you’re feeling really great today, you may inadvertently spread the joy to someone you don’t even know.
Recent research, published in the British Medical Journal, used data from the Framingham Heart Study to recreate a network of 4,739. James Fowler, professor of political science at the University of California in San Diego and co-author Nicholas Christakis of Harvard Medical School charted friends, spouses and siblings in the network, and used their self-reported happiness ratings from 1983 to 2003.
“Imagine several pebbles thrown into a pool of water that send ripples outward,” said Fowler. “Each pebble represents a happy person and the waves the impact of that person’s mood on others.” This impact, his study found, extends through several degrees of separation, to the friends of a person’s friends. That means when you feel happy, a friend of a friend of a friend has a slightly higher likelihood of feeling happy too.
“The lesson is that taking control of your own happiness can positively affect others,” said Fowler. “We get this chain reaction in happiness that I think increases the stakes in terms of us trying to shape our own moods to make sure we have a positive impact on people we know and love,” he said.
Sadness also spreads in a network, but not as quickly, the researchers found. Each happy friend increases your own chance of being happy by 9 percent, whereas each unhappy friend decreases it by 7 percent. This reflects the total effect of all social contacts.
When framing the question differently, the study found that you are 15 percent more likely to be happy if a direct connection is happy, 10 percent if the friend of a friend is happy, and 6 percent if it’s a friend of a friend of a friend.
This report adds to the considerable research on emotional contagion, the tendency to express and feel emotions that are similar to those of others. Happy people create happy people. Sad people create sad people. Disgruntled employees create disgruntled employees. Emotions travel from person to person like a virus, and they travel fast.
Reference
Fowler, J. H. & Christakis, N. A. (2008). Dynamic spread of happiness in a large social network: longitudinal analysis over 20 years in the Framingham Heart Study. British Medical Journal, 337, a2338
