Michael F. Jacobson MIT Press, 296 pages, $26.95 It will not surprise you in the slightest that there’s a white crystal scourge eroding the health and mental wellbeing of the nation. It might however surprise you to know that you, dear reader, almost certainly consumed too much of this dangerous substance yesterday. I’m not saying that this is how you got it, but they slip it into your chicken soup. Whether delivered as a crystal or a powder, this white substance harms everyone, but is worst for working class and vulnerable communities. That’s one reason why the Center for Science in the Public Interest (CSPI) — along with other health and welfare groups — has, for decades, tried to bring consumption down to at least a reasonable scale, battling to limit its uncontrollable sale and consumption. This has been to little avail as the experience of consuming this substance — enshrined in many ancient cultures — is delightful and it makes everything else better.