Do daily prayers or meditation help protect against cardiovascular disease? How about believing in a benevolent God — does that help with hypertension?

The scientific study of the relationship between religion and health is a wild forest, full of results that often contradict each other.  At one moment, private devotions seem to clearly help with health. But then the next study comes out and suggests that it’s not private religious practices, but a mixture of personality and social support. Trying to get a grip on the research is a dizzying task.

But through all that complexity and the contradictions, there’s one clear signal that has persisted since this research began nearly a century ago: religious attendance predicts lower rates of mortality. In other words, physically going to your mosque, temple, church, or place of worship continually predicts a longer life. Why would this be the case?

Early on, the association between religious attendance and mortality held primarily because it was the easiest part of religion to study. It’s much easier to ask people how often they go to religious services than other, more personal questions.  So it seemed likely that some other factor was lurking beneath the surface.

That would make sense – after all, religious practices like Mormons abstaining from alcohol, coffee, and tobacco, or Seventh-day Adventists’ vegetarianism must have a greater impact on health than just going to temple.  Or it could be a more psychological factor that’s really driving the association – belief in a moral order and purpose or a felt connection to one’s ancestors could give people a sense of well-being that helps reduce stress and thereby increase their life-span.

And yet, while these other factors do impact health and mortality, none of them explained the relationship.  In other words, there wasn’t something else going on beneath the surface; it really did have to do with just showing up.

One of the leading researchers in this field, Harold Koenig, analyzed the results from hundreds of these studies, and found that people who attended religious activities at least once a week have a 37% lower mortality risk than those with less frequent attendance. This is the sort of mortality risk reduction associated with not smoking or regular exercise.

Importantly, the association also holds across different religious traditions. This suggests that the content of religious belief and the types of practices, which varying wildly across traditions, aren’t the most salient factors. After decades of research, it’s incredible to get results like this that remain consistent rather than unravel under scrutiny.

Not only has the relationship held throughout time, it also holds when controlling for other variables. Remember, it’s not just a matter of belief or social support or psychological comfort or prescribed health practices.  While all these factors contribute to the 37% reduction, they aren’t the whole story. So, what else is going on here?

The message that I hear within this research is that connection matters.  Being connected to a community, to something larger than you, carries benefits that extend beyond those we can pin down and track.

Not only does connection matter, but that connection isn’t just a random or imagined bond – it requires actually showing up. Remember, it is attendance not affiliation that drives the relationship. This point seems to echo the famous (at least in some circles) “Roseto effect.”

In the mid-20th century, health researchers became fascinated with Roseto, Pennsylvania because this village defied all common reason. The inhabitants of Roseto smoked and drank regularly, worked in quarries, fried their food in lard, and faced discrimination – not exactly the model of health. But despite all this, they still tended to live way longer than folks in the neighboring towns.

It turns out, the important difference was the community – Roseto was a close-knit village of recent Italian American immigrant. The sad end to this story is that as each subsequent generation became more Americanized and branched out from this tightly-knit social network, the health effect vanished.  Despite the sad end, the lesson remains: being connected to a tight social group leads to better health.

Perhaps religious attendance is another version of the Roseto effect, since religious communities offer one of the few opportunities to be part of a regular social group beyond work and family. And while religious communities certainly aren’t the only ways to come together, the key is that being connected makes a difference.

So if we simply show up and be present with others, we might not just become spiritually healthier. We might become physically healthier, too.

(This post is part of the Sinai and Synapses Discussion Forum, a collection of perspectives on specific topics. It is part of our Fall 2016 series, “When Religion Heals, When Science Heals.”)