It doesn’t seem to matter how many diet books get published or how much consumer-friendly advice is offered on the talk shows – we still don’t seem to grasp what makes us overweight and what we can do about it. Rather, several myths dominate our thinking and we are perennially asking the same questions. Why is it so difficult to lose weight and keep it off? What’s more important: carbs or calories? What's behind the obesity epidemic and how have some people maintained a healthy weight? Understanding what the science actually shows is an essential step towards the body size that’s right for you.