The figures were produced after the records of more than 74,000 women who took part in the US Nurses’ Health Study were examined. They were mostly Catholic or Protestant Christians with the numbers of women of different faiths too small to draw statistically significant conclusions.
In a paper in the journal JAMA Internal Medicine, the researchers wrote: “Compared with women who never attended religious services, women who attended services more than once per week had a 33 per cent lower mortality risk.
“In examining the potential pathways from religious service to all-cause mortality, we found that depressive symptoms, smoking, social support, and optimism were potentially important mediators.”
However they added: “No single mediator explained more than about 25 per cent of the effect. There may be many pathways from attendance at religious services to health.”
The academics stressed this did not mean doctors should tell their patients to go to church.
“Our results do not imply that health care professionals should prescribe attendance at religious services, but for those who already hold religious beliefs, attendance at services could be encouraged as a form of meaningful social participation,” they wrote.
The average baseline age of the people studied was 60 and there were more than 13,500 deaths during the 16-year period of the study.
Dr Dan German Blazer, writing in commentary article in the same journal, said the study “does not address philosophical or theological questions such as ‘Does God (or any higher being) exist?’”
And he added: “The data do not validate claims made about some of the positive benefits of specific religious experiences, claims made even by medical professionals.
“Reasons for attendance at religious services may vary appreciably across individuals, such as religious devotion, lifelong habits, social pressures, and perhaps simple loneliness causing individuals to search for a support group with which to connect.
“We have no assurance that attendance at religious services is a marker of the strength of one’s religion or spiritualty and no description of the extent of private practices of spirituality, such as prayer, or perceptions of spiritual well-being among the participants.”
He said the study “cannot be generalised to men or to young adults” or “other religious groups, such as Jews, Buddhists, Muslims, and Hindus” because the people it described were mostly older female Christians.