One should always, always be a little wary when reading health advice in popular news/opinion type sites. Slate might be well respected in certain areas of politics/popular culture/whatever (I have no idea, really, they might be, they might not be). On the topic of antioxidants, this is something I've heard rumblings about for a while. If I wasn't feeling quite so lazy at the moment, I'd go and dig out the references I've got stashed somewhere. However, I am lazy. If I recall correctly though, the stuff I've seen so far an anti-oxidants is more along the lines of them being useless rather than harmful. This article only hinted them being harmful, something to possibly investigate if a)I was actually deliberately taking antioxidants for health benefits and b)I wasn't quite so lazy at the moment. The more pressing harm, is noted at the end of the article, in that the trust between doctors and patients is broken down when the public are convinced of the effectiveness of anti-oxidants despite the advice of their physicians. Similar to how one of the the biggest harms of homoeopathy is that people who believe in it, neglect to get proper medical advice.