In a nutshell: Eating, ultimately, is about feeding cells in our body. Hunger is internal starvation. We overeat when our metabolism doesn't liberate fat stores fast enough, resulting in cellular starvation, and hence hunger. Carbs inhibit this process by stimulating too much insulin and insulin resistance. This is culminative, and in the worse case results in diabetes.
One likely proof? Low-carb diets don't induce hunger, indicating cells are being fed from internal stores. Internal food (fast) versus external food are roughly the same from a hunger perspective. And if that internal food is inhibited, more hunger, more eating. More proof: fasting is relatively easy once the body adjusts. Hunger goes away.
This book reviews all the key diet and obesity research and their associated strengths, weaknesses, and contradictions. You will likely be convinced after reading it, and learn a ton about health, science and human nature. One strikingly obvious lesson- good science, and good scientists, don't engage in the self-promotion and pet-theory mongering that, unfortunately, seem to be noticed by media and government and become public policy. The second- public policy and the status quo have a huge influence on the beliefs and outlooks of a research community.
My personal epiphany was thinking about eating as cellular nutrition, and thinking about fat stores as important energy stores, not unwanted side effects of eating. A lot of studies in the book show convincingly show hunger is cellular-need driven- both fuel and nutrients- and this opens up important new perspectives.
A few other influences on the current mess outlined nicely in the book through copious reviews of studies:
1) When you remove fats, you add carbs. You need to eat something, right? Michael Pollan raises this point nicely as well in "In Defence of Food"- when you remove something, consider what replaces it.
2) much research that showed higher fat leading to higher disease ignored the prevalence of higher refined carbs. This was the switch all interpretations turn on, and without controlling for it, renders the low-fat diet conclusions reached by these studies as unsupportable and downright dangerous.
3) the assumption that fat was more fattening due to being calorie dense (9 calories versus 4 for carbs and proteins) is absolutely wrong. This was an important secondary influence on pushing low fat diets.
Sadly, this was all known 50 years ago, and ignored due to cholesterol and fat and other red herrings. Once fat was the demon, carbs had to be the angel. And what did we get? An obesity epidemic unlike any seen in history.
This book is beautifully written, and a great, engaging read. I found one awkward chapter in the middle- Paradoxes- but it made sense when I read later chapters. It was summarizing the research covered so far, and laying down the hypothesis for the remainder of the book.
Read this book. It might save your life.