Nobody disputes the obvious fact that it is possible to make anyone lose weight - starvation is one classic method that has been around for a long time. But that isn't the problem. We know how to make a person thinner, but we don't know how to make people thinner, because people like to eat fatty foods, they like to be sedentary, they dislike dieting and often don't have the willpower for it. Having an effective diet is only part of a solution if people are resistant to it.

Saying calorie restriction is a way to make people thinner is like saying quitting cigarettes is a way to lower cancer rates: not true enough.