The Salt
3:28 pm
Wed May 16, 2012

Can Coffee Help You Live Longer? We Really Want To Know

Originally published on Wed May 16, 2012 6:49 pm

It seems like every day there's some new research about whether our favorite drinks are good for us. One day, science says a glass of red wine a day will help us live longer. The next day, maybe not. It seems journalists are pretty interested in wine research, as Deborah Blum over at the Knight Science Foundation recently pointed out, and the same might be said for coffee.

In fact, the latest installment in the long saga of coffee just came out, and of course, we're on it. It's a big new study that found that people who drink java appear to be less likely to die prematurely than those who don't.

Now, there's been a lot of research into whether coffee's good for our health. "The results have really been mixed," acknowledges Neal Freedman of the National Cancer Institute, who led the study published in The New England Journal of Medicine today. "There's been some evidence that coffee might increase the risk of certain diseases and there's also been maybe more recent evidence that coffee may protect against other diseases as well."

So to clarify the field a bit, Freedman and his colleagues undertook the biggest study yet to look at the relationship between coffee and health. They analyzed data collected from more than 400,000 Americans ages 50 to 71 participating in the NIH-AARP Diet and Health Study.

"We found that the coffee drinkers, they had a modestly lower risk of death than the non-drinkers," he tells The Salt.

Here's what he means by "modestly:" Those who drank at least two or three cups a day were about 10 percent or 15 percent less likely to die for any reason during the 13 years of the study. But you don't necessarily need to be a heavy coffee drinker.

"Starting with those drinking a cup a day or more then there started to be this inverse association," he said.

When the researchers looked at specific causes of death, coffee drinking appeared to cut the risk of dying from heart disease, lung disease, strokes, injuries, accidents, diabetes and infections.

Now, Freedoman stressed that the study doesn't prove coffee can make people live longer. A study like this can never prove a cause-and-effect relationship. All it can really do is point researchers in the right direction for further investigation.

And even if it turns out that coffee is really good for you, scientists have no idea why. (That might be tomorrow's study.)

They do know it's not caffeine — decaf was just as good in the study. But Freedman says there are lots of other candidates for the potentially protective effects.

"It's estimated that there are more than 1,000 different compounds in coffee. And each one of them may affect coffee in different ways," he says.

For example, coffee contains antioxidants, as well as substances that appear to play a role in diabetes, he said.

Freedman also noted that the study could not tease apart whether different types of coffee — corporate office drip versus French press, for example — might differ.

Until scientists do more research, Freedman doesn't recommend anyone start drinking coffee, or drink more coffee. But at the very least the new findings, he said, provide a little reassurance that coffee lovers aren't hurting themselves by indulging in a couple of cappuccinos or lattes every day.

Copyright 2012 National Public Radio. To see more, visit http://www.npr.org/.