Caffeine. You know it, you love it. And thanks to new research, we now have a better idea of how some plants evolved to make it. Caffeine, a two-ringed, carbon- and nitrogen-based molecule, shows up ...

For many people, the aroma of freshly brewed coffee is the start of a great day. But caffeine can cause headaches and jitters in others. That’s why many people reach for a decaffeinated cup instead. I ...