Eating well is not just a matter of knowing what’s best for your health, although that is a good place to start. It is also about understanding the body’s metabolism and how messages sent by the brain can wash away the most determined efforts at willpower. Take neuroscience, blend it with corporate marketing and the ready availability of food, and we have the recipe for making chocolate-chip cookies seem a lot more appealing than steamed vegetables. What roles do personal responsibility and government regulation play in healthy eating? Why is dieting so hard? What foods will satisfy us?