Religious people are more satisfied with their lives than nonbelievers, but a new study finds it's not a relationship with God that makes the devout happy. Instead, the satisfaction boost may come from closer ties to earthly neighbors.

According to a study published today (Dec. 7) in the journal American Sociological Review, religious people gain life satisfaction thanks to social networks they build by attending religious services. The results apply to Catholics and mainline and evangelical Protestants. The number of Jews, Mormons, Muslims and people of other religions interviewed was too small to draw conclusions about those populations, according to study researcher Chaeyoon Lim, a sociologist at the University of Wisconsin-Madison.

"We show that [life satisfaction] is almost entirely about the social aspect of religion, rather than the theological or spiritual aspect of religion," Lim told LiveScience. "We found that people are more satisfied with their lives when they go to church, because they build a social network within their congregation."

Happiness is a crowded pew

Many studies have uncovered a link between religion and life satisfaction, but all of the research faced a "chicken-and-egg problem," Lim said. Does religion make people happy, or do happy people become religious? And if religion is the cause of life satisfaction, what is responsible — spirituality, social contacts, or some other aspect of religion?

Lim and his colleague, Harvard researcher Robert Putnam, tackled both questions with their study. In 2006, they contacted a nationally representative sample of 3,108 American adults via phone and asked them questions about their religious activities, beliefs and social networks. In 2007, they called the same group back and got 1,915 of them to answer the same batch of questions again.

The surveys showed that across all creeds, religious people were more satisfied than non-religious people. According to the data, about 28 percent of people who attended a religious service weekly were "extremely satisfied" with their lives, compared with 19.6 percent of people who never attended services.

But the satisfaction couldn't be attributed to factors like individual prayer, strength of belief, or subjective feelings of God's love or presence. Instead, satisfaction was tied to the number of close friends people said they had in their religious congregation. People with more than 10 friends in their congregation were almost twice as satisfied with life as people with no friends in their congregation.

Are church friends special?

Importantly, Lim said, the study suggested a causal link between religion and life satisfaction: People who had started attending church more often between the 2006 and 2007 surveys became happier. Again, the happiness was explained entirely by a boost in close church friendships.

"We think it has something to do with the fact that you meet a group of close friends on a regular basis, together as a group, and participate in certain activities that are meaningful to the group," Lim said. "At the same time, they share a certain social identity, a sense of belonging to a moral faith community. The sense of belonging seems to be the key to the relationship between church attendance and life satisfaction."

While a higher number of secular close friendships were also associated with life satisfaction, church friendships seem to involve something that lifts satisfaction even more, Lim said. Additional research by Lim and Putnam, reported in the book "American Grace: How Religion Divides Us and Unites Us" (Simon & Schuster, 2010), has found the religious propensity toward charity and volunteerism to be connected with close church friendship, as well.

Theoretically, Lim said, belonging to a secular friend group that engages in meaningful activities and shares a social identity might also boost life satisfaction. The researchers plan to carry out a third round of surveys with the same group of participants in 2011 in which they hope to gather data on secular friendship groups.

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