Caffeine is a psychoactive, but is it addictive?

Caffeine is the world’s most popular psychoactive drug, but how much is too much? And is it dangerous? Here’s what the science says about all that coffee and tea you’re consuming. SUBSCRIBE: FOLLOW QUARTZ: Facebook: Twitter: Check out the rest of our videos: Quartz is a digitally native news outlet dedicated to telling stories at the intersection of the important and the interesting. Visit us at to read more.