DEAR DOCTORS: I think that as I get older, I may be developing a sensitivity to caffeine. If that's actually something that can happen, it will make me very sad. I have always loved my cup of coffee in the morning, but now I find that it makes me a bit racy. I would love to understand why.
DEAR READER: We join you, along with billions (yes, billions-with-a-b) of people throughout the world in your devotion to caffeine. Whether it's coffee, tea or other caffeinated beverages, we humans love the lift it gives. Recent data estimate that 85% of adults in the United States consume caffeine in some form each day.
