“Joining a religious group may do more to offer ‘sustained happiness’ than other forms of social participation. Researchers in the Netherlands, analyzing 9,000 Europeans over age 50, looked at four areas: volunteering or working for a charity; taking educational courses; participating in a religious organization; and participating in political organizations. Taking part in a religious organization was the only one of the four that resulted in sustained happiness. The researchers were’t able to conclude whether the benefits came from the religious organizations themselves or from faith.”
From the “Century Marks” column of Christian Century, 16 September 2015 edition, page 8.
Another possibility could be that happier people are more likely join religious organizations, but maybe if you’d like to be happier, you could give a religious organization a try.