There are few news subjects more reliably depressing than nutritional science.  A glance at the headlines will tell you that sugar is bad for you, red meat is bad for you, and alcohol is really, really bad for you. The message seems to be that if a food or drink gives you even an iota of pleasure, it’s almost certain that your body will pay for it, sooner or later. But there is one exception, a glorious concoction that was first consumed in ninth-century Ethiopia, that fueled the Age of Enlighte