I'm quite enjoying these statistics-based posts I've been doing lately. And I just figured out why: because it's totally countercultural! If the whole world is running on idiotic rumours and half-baked opinions, it's kind of fun to do the exact opposite.
Today I have an easy one: people have often commented that even though I don't drink coffee, I get plenty of caffeine because I drink plenty of soft drinks, so I'm not really any different. My answer is always, "don't soft drinks have a lot less caffeine, though?" And then the conversation dies because nobody really knows.
Well, here's the answer: coffee has about 6.4 times as much caffeine per volume than coke. I don't drink 6.4 times as much coke as you drink coffee, that's for sure. Also, green tea has about 25% more caffeine than coke, but less sugar (unless you add it), so it's probably even less of an upper. Tazo Chai has about double that, or 1/3 as much as coffee.
And there's actual evidence that caffeine makes insomnia worse (surprise), so that could help explain why I sleep better than a lot of my friends.
On relative availability of information
The web contains about a zillion sources of information about how much caffeine there is in everyday household items, which is mostly unimportant.
But I had to search for a long time to find even vague trend information about gasoline prices, which are earth-changingly important.
Not surprisingly, people act a lot more religiously in debates about oil/gas and environmental trends (with almost no information) than debates about caffeine.