Rob M. van Dam, assistant professor at Harvard Medical School and Harvard School of Public Health in Boston, conducted a study to evaluate a possible link between women's risk of stroke and coffee consumption. Data from the Nurses' Health Study conducted from 1980 to 2004 and involving more than 83,000 women at an average age of 55 was reviewed. None of the women participating in the study reported a history of stroke, heart disease, diabetes or cancer prior to the study. Every two to four years, they completed "food frequency" questionnaires about their diets. The surveys showed that 84 percent drank some caffeinated coffee each day, with 78 percent drinking tea and 54 percent reporting that they drank soft drinks with caffeine. In addition 50 percent reported drinking decaffeinated coffee. Over the study time span of 24 years, there were 2,280 strokes documented, more than half of which were ischemic strokes that resulted from the blockage of blood vessels.

As the study co-authors reported, those women who drank at least four cups of coffee each day reduced their risk of stroke by 20 percent compared to study participants who drank less than one cup each month. "Many people have been very concerned that coffee might actually be a risk factor for stroke, that it might, in fact, increase the risk of stroke," says van Dam. "But here we saw that it might end up being beneficial rather than detrimental." The study also found that the same benefits did not apply to those participants who smoked. Although researchers have yet to identify what component in coffee reduces the risk of stroke, they believe it is something other than caffeine, as caffeinated tea and soft drinks did not yield the same benefit.

The researchers cautioned that more research is needed and noted that such conditions as insomnia, anxiety, high blood pressure and cardiac complications can be negatively affected by coffee consumption. According to van Dam, the findings are early, but he says: "The data we do have is very convincing in the sense that we feel comfortable that we definitely found no association between high coffee consumption and a higher stroke risk. So women can continue to enjoy their coffee and focus on other things to reduce stroke risk, such as engaging in more physical activity, reducing salt intake and stopping smoking."

News Release: Drinking coffee may help to ward off a stroke www.healthnews.com February 17, 2009