Women who attend religious services more than once each week live 33 percent longer than women who don't, according to a new study from the Harvard T.H. Chan School of Public Health.
The study published in the JAMA Internal Medicine journal further recommends that doctors could seriously begin exploring religion and spirituality as a resource for patients.
"Frequent attendance at religious services was associated with significantly lower risk of all-cause, cardiovascular, and cancer mortality among women. Religion and spirituality may be an underappreciated resource that physicians could explore with their patients, as appropriate," the study concluded.
A release from Harvard on the study noted that nearly 40 percent of Americans report attending religious services once per week or more. While previous studies have suggested a link between attendance and reduced mortality risk, many were criticized for major limitations, including the possibility of "reverse causation"— that only those who are healthy can attend services, so that attendance isn't necessarily influencing health.
This new study, said the release, addressed those concerns by using rigorous methodology that controlled for common causes of attendance and mortality, used a larger sample size, and had repeated measurements over time of both attendance and health.
The study used data from 74,534 women who participated in the Nurses' Health Study from 1992-2012. During the period, the women answered questionnaires every two years about their diet, lifestyle, and health and reported on their religious service attendance every four years. The researchers then adjusted for a number of factors, including diet, physical activity, alcohol consumption, smoking status, body mass index, social integration, depression, race and ethnicity and the results suggests religion is good for a longer life.
"Our results suggest that there may be something important about religious service attendance beyond solitary spirituality," Tyler VanderWeele, professor of epidemiology at Harvard Chan School and senior author of the study, noted in the release. "Part of the benefit seems to be that attending religious services increases social support, discourages smoking, decreases depression, and helps people develop a more optimistic or hopeful outlook on life."
Other Harvard Chan School authors involved in the study included lead author Shanshan Li, postdoctoral researcher in epidemiology; Meir Stampfer, professor of epidemiology and nutrition; and David R. Williams, Florence Sprague Norman and Laura Smart Norman Professor of Public Health.
Compared with women who never attended religious services, women who attended more than once per week had 33 percent lower mortality risk during the study period and lived an average of five months longer, the study found. Those who attended weekly had 26 percent lower risk and those who attended less than once a week had 13 percent lower risk.
The study also found that women who attended religious services once per week or more had a decreased risk of both cardiovascular mortality, 27 percent, and cancer mortality, 21 percent.
The release noted, however, that the study consisted of mainly white Christians and therefore may not be generalizable to the general population, other countries, or areas with limited religious freedom. It further noted that the study population included only U.S. nurses of a similar socioeconomic status, who tend to be fairly health conscious.