Does chocolate cause acne?
Lots of people think it does, lots of doctors even think it does. But dermatologists say it doesn’t. To decide which side is correct we need to look at the evidence, and unfortunately the evidence is about as thin as it gets.
There is only a single decent study of chocolate and acne. This is quite remarkable when you think about it, given that acne affects nearly all adolescents and about half of adults over 25. But when you realise that only 12% of middle-aged women and a tiny 3% of middle-aged men suffer it becomes clear who writes the cheques for medical research. Millions of dollars are poured into the development of little blue pills and hair tonics; the pimply teenagers are left to fend for themselves.
Perhaps those teenagers can console themselves with a bar of chocolate, because that one study does conclude that there is no link between chocolate and acne. That doesn’t mean chocolate is entirely off the hook. The big problem with the study is that it compares subjects who ate chocolate bars with subjects who ate bars similar in every way except that they contained no cocoa. There was no third group who didn’t eat any bars at all. Which leaves open the possibility that the fat and sugar in chocolate exacerbate acne even if the cocoa doesn’t.
There is not much more evidence about fat and sugar than there is about chocolate. In many non-western societies acne is unheard of, which leads some to suggest our diet is to blame. But there are lots of other differences too — why pick on diet? Further evidence is emerging though, including a recent trial that links acne to the glycemic index, a measure of how much food affects blood glucose levels. And it turns out that while the western diet has a high glycemic index, the pimple-free peoples of the world generally enjoy a diet with a low glycemic index.
So maybe chocolate does cause acne — along with ice cream, chips and all the other usual suspects. Chocolate in particular, though, doesn’t.