I heard recently that an apple have more caffeine than a cup of coffee. This struck me as a crazy claim so I decided to investigate. It turns out that it is indeed a crazy claim. An apple has no caffeine in it at all, but if you google the question it yields over one and a half million hits, so there is plenty of confusion out there. On the bright side the top hits all debunk the myth of apples having more caffeine.
It seems that the question derives from the idea that with or without caffeine an apple will wake you up just as well as a cup of coffee. A little bit more plausible, but not much more. I think this is believed because the apple has a decent amount of sugar in it – roughly the same as 6 ounces of coke. This is far more than a cup of coffee has since coffee in turn has no sugar unless you add some. Of course, at risk of stating the obvious coffee will have more sugar in it than an apple if you add more sugar and less if you do not.
If you add no sugar, which one will wake you up more – as coffee is a stimulant and sugar is a stimulant? Well, my experience suggests that coffee will wake you up far better, but that neither one will have a major impact on me if I am regularly drinking coffee and eating foods with sugar in them (and while I do not have much of a sweet tooth, I do not imagine I have ever gone through a day without taking in any sugar in some form or another having never fasted).
I cannot think of a single time that I ate an apple, though, and felt like it gave me a buzz whereas if I do not drink coffee for a while even one cup of coffee will give me a nice buzz so my personal experience suggests the answer is obvious, but perhaps it is just that - personal - or perhaps it is just something fun to claim to see how it surprises people.