We have lost our way in western society and forgotten how to eat real food and stay healthy. The author's advice is simple and powerful "Eat food. Mostly plants. Not too much."
Michael Pollan does a tremendous job of making nutritional gibberish into plain English. He has done lots of research and even suggests ways you can eat food and be healthy while doing it. Cons: It gets a little biased at times, in my opinion. At times, it can also be repetitive to the point of boredom.