Nudge: Improving Decisions About Health, Wealth, and Happiness by Richard H. Thaler and Cass R. Sunstein - This book is groundbreaking in defining a class of simple and powerful ways to change human behavior, without limiting people's freedom.
Lessons from the Fat-o-sphere: Quit Dieting and Declare a Truce with Your Body by Kate Harding and Marianne Kirby - An empowering -- and scientifically accurate -- guide to fat acceptance. Every living human should read it, no matter what they weigh.
Food Rules: An Eater's Manual by Michael Pollan - Simple, commonsense rules for eating. Stop counting calories and worrying about vitamins. Follow these rules and everything will be ok.