Regular attendance at religious services could have an added benefit: a longer life. That's the word from Harvard researchers, who found that women who went to church at least twice a week were 33 percent less likely to die over the 20-year study period, compared with those who never attended, reports HealthDay News.

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Is this due to the power of religious belief? Probably not. Instead, it's the benefits that come with being part of a community of faith and the communal practice of worship, says study leader Tyler VanderWeele, a professor of epidemiology at the Harvard T.H. Chan School of Public Health in Boston.

The study: Drawing data from the Nurses' Health Study, which began in 1976 and includes 75,000 U.S. women, the Harvard team studied women between the ages of 30 and 55 years, focusing on their lifestyle, health and religious practices between 1992 and 2012. All the women were white and either Roman Catholic or Protestant. During the 20-year study period, more than 13,500 women died.

The data were adjusted to account for diet, physical activity routines, drinking and smoking history, weight, depression, social life and race.

The results:

• Women who attended worship at least once a week had a 27 percent lower risk of dying from heart disease and a 21 percent lower risk of dying from cancer, compared with those who never attended.

• Overall, the risk for dying dropped by 26 percent for those who attended worship weekly, while those who went less frequently saw their risk drop by 13 percent, compared with those who never attended.

• Meanwhile, women who attended church more than once a week had a 33 percent lower risk of death, compared with those who never attended.

• In addition, those who regularly attended religious services had fewer symptoms of depression and were far less likely to smoke.

Why does church attendance make a difference? The longevity benefit is probably due to a boost in social support and a heightened sense of self-discipline, combined with a lower risk for depression.

Interestingly, private religious practices and a sense of spiritual identity offer no discernable health benefits. "These things may of course still be important and meaningful within the context of religious life, but they do not appear to affect health as strongly," VanderWeele told HealthDay News. The results from our study suggest that there may be something important about religious service attendance beyond solitary spirituality."

One caveat: The research showed an association between regular attendance at worship services and longevity, not a cause-and-effect relationship.

The study findings were published in the journal JAMA Internal Medicine.

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