“Which has more caffeine--tea or coffee?

Maybe it is a reflection of our constant struggle to ward off sleep, or simply the desire for that scintillating buzz that comes from a good cup of Joe. In the United States, more than 80 percent of people consume caffeine in one form or another every day. Worldwide it is the most popular drug, far ahead of nicotine and alcohol. Some anthropologists speculate that its use may date as far back as the Stone Age.”