Sweet Poison: Why Sugar Makes Us Fat by David Gillespie, Penguin Books, 2008. Link is to the book’s page on the author’s website. Some parts of this website are subscription only.
You’ll find quite a few books about food and nutrition as this book blog continues. (I’m reading a book titled The Big Fat Surprise: Why Butter, Meat & Cheese Belong in a Healthy Diet; it should show up soon.) David Gillespie is the most accessible writer I’ve found on the subject of the evils of sugar. Robert Lustig’s Fat Chance and Gary Taubes’ Why We Get Fat: and What to Do About It are both good resources but very dense. You have to be pretty interested in the subject already in order to be motivated to plow through them. Gillespie, on the other hand, is funny, smart, and brief, and he plentifully illustrates his ideas from his own experience. I have to admit that I did a little skipping in the chapter “Biochemistry 101,” but he does an admirable job of explaining the actual processes by which our bodies transform food into energy.