Rock Doc

My day starts with coffee. I'm too cheap to buy it by the cup from baristas, so I just brew my own Folgers by the pot. I have a cup or two as I settle into work each morning, and another cup - sometimes two - in the early afternoon. That may not be wise for a chronic insomniac like myself, but it's a lifelong habit that at this point would be quite tough to break.

I'm in good company as a coffee-drinker. Coffee is one of the most popular beverages on the planet. That means that coffee's effects on the human body are worthy of medical study.

Over the years you may have seen headlines about the...