Coffee and heart health: How many cups of caffeinated coffee are safe to drink each day?

Previous studies have found that caffeine is the world's most popular stimulant and psychoactive substance, and coffee is the most common way people consume caffeine.

The latest research supports the conclusion that, for most adults, consuming up to 400 mg of caffeine a day (or up to five 8-ounce cups of caffeinated coffee per day) is safe and appears to be linked to a lower risk of cardiovascular disease for some individuals.

However, higher doses of caffeine, such as levels found in energy drinks including energy shots, may cause cardiovascular harm, according to a new American Heart Association scientific statement, "Caffeine and Cardiovascular Disease," published today in the journal Circulation. ...