Good news for caffeine addicts: Green tea and coffee both apparently help reduce the risk of suffering a stroke, reports NPR. A new study of more than 82,000 adults in Japan found that for coffee drinkers, just one cup a day lowers the chances of a stroke 20%. And for green tea, more is better, with four cups a day lowering the risk by 20%. Five or more cups of green tea a day was found to reduce death from cardiovascular disease by 26% and overall mortality by 15%, notes the Atlantic.
Green tea contains compounds that help regulate blood pressure, improve blood flow, and have an anti-inflammatory effect; coffee is thought to also contain different helpful compounds. Back in the 1980s, doctors often advised against caffeine altogether. But it turns out those studies did not check for one very important variable—smoking. Back then, coffee drinkers were also heavy smokers. "So it made coffee look bad in terms of health outcomes," explains one researcher. (Read more coffee stories.)