PITTSBURGH (KDKA) — Got coffee on the brain?

It might be a good thing, if you’re a woman.

More than a cup a day is associated with a lower risk of stroke, according to a study in the journal “Stroke.”

Researchers in Sweden followed nearly 35,000 women ages 49 to 83 for 10 years. The women filled out questionnaires about coffee consumption.

Women who drank more than a cup of coffee a day had a 25 percent lower risk of stroke than those who drank less.

“Hypotheses have been made as to whether it’s the antioxidants effect of coffee itself, or whether it’s caffeine, and so I think further studies need to be made looking at caffeine specifically and sort of the result of taking caffeine, and whether that causes more or less strokes, more or less heart attacks,” says Dr. Hebah Hefzy.

Of course, some people need to be careful to avoid an abnormal heart rhythm that can lead to stroke.

“Caffeine has been linked to hyperthyroidism, and hyperthyroidism can increase atrial fibrillation,” Dr. Hefzy explains, “and so I think certain subsets of people that have particular medical conditions really do need to be careful with the amount of caffeine that they drink.”

Studies like these can’t prove cause and effect, but present an interesting pattern.

“People who don’t drink coffee, I never recommend that they do to prevent stroke,” says Dr. Hefzy, “because I have no evidence that it really works.”

She points out that other studies have shown a decreased risk of diabetes with caffeinated coffee — a pattern seem not just with women, but also with men. But why these patterns are seen isn’t clear, and further study will be needed to figure this out.

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