A new study by the Harvard T.H. Chan School of Public Health and published online in JAMA Internal Medicine found that women who attended religious services more than once a week were more than 30% less likely to die during a 16-year-follow-up than women who never attended.
The study also found that compared with women who never attended religious services, women who attended more than once per week had a decreased risk of both cardiovascular mortality (27%) and cancer mortality (21%).
“Our results suggest that there may be something important about religious service attendance beyond solitary spirituality,” said Tyler VanderWeele, professor of epidemiology at Harvard Chan School and senior author of the study. “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.”
Researchers looked at data from 1992-2012 from 74,534 middle-aged female nurses. From the study: “the sample is derived from female nurses who volunteered to participate in the study. These women are therefore better educated than the general population, more willing to participate in activities that are of value to the larger community given their volunteer status, and informed about health and health care in general.”
The women answered questionnaires about their lifestyle, diet and health every two years, and about their religious service attendance every four years. Researchers adjusted for a variety of factors, including diet, physical activity, alcohol consumption, body mass index, smoking, depression, race and ethnicity.
Most of the women in the study were Protestant or Catholic. The baseline age of the participants was 60 years or older – and “therefore the study cannot be generalized to men or young adults.”
The study concludes:
So what can we learn from this study? In this well-designed secondary data analysis, attendance at religious services is clearly associated with lower risk of mortality. This finding should not be ignored but rather explored in more depth. Are their confounding variables of importance not available to the investigators of this study? What possible mechanism may contribute to this association? Is attendance at religious services in some way associated with health habits critical to longevity that are not considered in this study? In other words, the study invites additional investigation, as the iterative nature of epidemiology so often does.