In 2006, a group of cardiologists at Harvard Medical School published the results of a ten-year study that cost $2.4 million to run. They called it the Study of the Therapeutic Effects of Intercessory Prayer. It involved 1,802 heart surgery patients across six hospitals. Some were prayed for by strangers in three Christian congregations. Some were not. Some were told they would be prayed for. Some were told they might be.

The study's question was simple. Does being prayed for help you recover?

The answer was also simple. No. The group prayed for had the same complication rate as the group that wasn't. Actually, the patients who were told for certain that strangers were praying for them did slightly worse, which the researchers attributed to performance anxiety.

This was supposed to settle the question. It didn't.

Because the more interesting research was already happening in a different direction.

Intercessory prayer is not the most interesting question

Praying for someone else's recovery without telling them, hoping for measurable medical outcomes, is what scientists call intercessory prayer. It has been studied many times. The results are mixed at best and mostly null. The 2006 Benson study was just the largest of these. Earlier studies (Byrd 1988, Harris 1999) found small positive effects that have not held up under replication.

If you came here wondering whether being prayed for makes your heart heal faster, the honest answer based on the best research available today is: probably not in any way researchers can measure.

But that's not what most prayer is.

Most prayer is something a person does themselves, often quietly, often alone, often with their eyes closed and their breathing slowed. That kind of prayer is much more interesting to measure. And the data there looks completely different.

What happens to the body when you pray

In 2003, the neuroscientist Andrew Newberg scanned the brains of Franciscan nuns at the moment they reported entering deep contemplative prayer. He found measurable activity changes in the parietal lobes (associated with the sense of self) and the frontal lobes (associated with attention). The nuns weren't making it up. Something was happening.

Other researchers have measured what happens in the rest of the body during sustained prayer:

These effects are not unique to prayer. Mindfulness meditation produces a very similar pattern. So does deep breathing on its own. So does Tai Chi. Researchers now group these together under the umbrella term contemplative practice, and the literature on contemplative practice is one of the more robust areas of mind-body research.

In other words: the act of praying, considered purely as a thing your body does, has measurable physiological effects. They are real and reproducible. They are also not specifically prayer's effects. They belong to a wider family of practices that ask you to sit still, breathe, and quiet your attention for a while.

This is not a debunking. It's the opposite. It means prayer has been doing something measurable in human bodies for two thousand years that researchers only started naming in the last forty.

What science doesn't measure

Here's where the column has to be careful.

The question "does prayer work" splits into two completely different questions, and confusing them is how most of the bad writing on this subject happens.

Question one: Does prayer have effects on the body and mind of the person praying that can be measured by a researcher with a stopwatch and a blood pressure cuff?

Answer: Yes. Repeatedly demonstrated.

Question two: Does prayer actually reach God, who actually exists, who actually hears it, who actually responds?

Answer: This question is not in science's domain. By design. Science measures what's measurable. Whether the universe contains a God who hears prayer is not a measurement question, it's a metaphysical one. Researchers studying contemplative practice are not pretending otherwise.

The honest position is to hold both at once. The physiological effects are real. The theological question is not what science is for. People who say "science proves prayer works" and people who say "science proves prayer is nothing" are usually selling you the same logical mistake from opposite sides.

What people who pray have said for two thousand years

The Christian tradition has, on the whole, been less interested in whether prayer "works" in a measurable sense than in what prayer does to the person who prays.

Augustine of Hippo, writing in the 4th century AD, said that prayer changes the one who prays, not the one prayed to. Teresa of Avila, writing in the 16th century, said the point of prayer was friendship with God, not getting things from him. Modern Christian writers like C.S. Lewis have made similar arguments: prayer is mostly about formation, not transaction.

This is, interestingly, what the research on contemplative practice tends to support. The most reliable effects of sustained prayer practice are on the person doing it. People who pray regularly report (and demonstrate, in measurable ways) lower stress, greater sense of meaning, better emotional regulation, and stronger social connection through their faith community.

Whether something else is also happening, whether God is also acting on the situation, is a question prayer's own tradition has long held to be irreducibly mysterious.

So does prayer work?

Here are the most honest answers, in order of confidence:

As a contemplative practice that affects the body: yes, measurably.

As a way to feel less anxious, more grounded, more connected: yes, for many people.

As a way to magically heal someone else from a distance: no, based on the best evidence available.

As communication with God: science doesn't have a way to measure this. The question is real. It is just not a science question.

The interesting part of the research isn't the yes or no. It's how thoroughly the data tracks what contemplatives have said for centuries. Prayer doesn't seem to be a wishing machine. It seems to be something closer to what its serious practitioners always said it was: a discipline that changes the person who does it, with measurable effects on the body and mind that come along for the ride.

That's a more interesting answer than either side of the usual fight tends to give.