RENEE MONTAGNE, HOST:
And here's some good news for those of us who live for that morning coffee, Steve - or, all right, also green tea. A new study of 82,000 men and women in Japan published in the medical journal Stroke found those in the habit of drinking green tea or coffee were significantly less likely to have a stroke. NPR's Allison Aubrey has more.
ALLISON AUBREY, BYLINE: The striking thing about this new study investigating coffee and tea consumption, is not that researchers found an association with less heart disease, it's the extent to which the habit seemed to protect people. Let's start with green tea. Physician Ralph Sacco, the past president of the American Heart Association, says in this study the more green tea a person drank the more it reduced the risk of suffering a stroke.
DR. RALPH SACCO: It's almost a 20 percent lower risk of stroke in the green tea drinkers.
AUBREY: Who drank four cups a day compared to those who rarely drank green tea. And with coffee, researchers found just one cup per day was also associated with about a 20 percent decreased risk of stroke within the next decade.
SACCO: It's a pretty important effect. It's a large study, so larger study more you can detect effects like this.
AUBREY: Now, Sacco says it's not just the Japanese who seem to benefit. Over the last few years, researchers in the U.S. have documented similar reductions in heart disease risk among Americans.
SACCO: The more accumulating evidence from a variety of studies, suggesting that green tea and coffee may be protective.
AUBREY: Studies suggest a coffee habit may also cut the risk of Parkinson's and Type 2 diabetes. Now, it's interesting to note that not long ago there was completely different thinking about coffee. In the 1980s many Americans were trying to avoid it. Caffeine was thought to be harmful, even at moderate doses. Harvard's Meir Stampfer says one reason for this is that back then coffee drinkers also tended to be heavy smokers.
And in early studies it was very tough to disentangle the two habits.
MEIR STAMPFER: So it made coffee look bad in terms of health outcomes.
AUBREY: As newer studies began to separate out the effects of coffee and tea, a new picture emerged: one suggesting benefits, not risks. Now, the Heart Association's Ralph Sacco says there's still a lot to learn here. Researchers haven't nailed down all the mechanisms by which coffee and tea influence our health.
And he says when it comes to preventing strokes and heart attacks, no one food or drink is a magic bullet. It's our overall patterns of eating and exercise that are important.
SACCO: It's really a whole lifestyle approach, and we need to remember that.
AUBREY: So if you are already in the habit drinking coffee or green tea, this study is one more bit of evidence that you can go ahead and enjoy it. Allison Aubrey NPR News.
MONTAGNE: This is MORNING EDITION from NPR News, made possible by this cup of coffee. I'm Renée Montagne.
STEVE INSKEEP, HOST:
And I'm Steve Inskeep.