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Two Reasons Why We Get Fat

I’m re-reading the excellent Why We Get Fat: And What to Do About It, by Gary Taubes and will be sharing lots of my notes and highlights.

So let’s get right to the good stuff. While there will be outliers and complications, the truth is that most of us get fat for two simple reasons:

  • when insulin levels are elevated, we accumulate fat in our fat tissue
  • our insulin levels are determined by the carbohydrates we eat

The more detailed explanation from Why We Get Fat (emphasis mine):

First, when insulin levels are elevated, we accumulate fat in our fat tissue; when these levels fall, we liberate fat from the fat tissue and burn it for fuel.

Second, our insulin levels are effectively determined by the carbohydrates we eat–not entirely, but for all intents and purposes. The more carbohydrates we eat, and the easier they are to digest and the sweeter they are, the more insulin we will ultimately secrete, meaning that the level of it in our bloodstream is greater and so is the fat we retain in our fat cells.

Carbohydrate is driving insulin is driving fat,” is how George Cahill, a former professor of medicine at Harvard Medical School, recently described this to me.

So there you have it. Control your insulin levels and you can control your fat. Hopefully the book will cover how to control insulin levels in more detail (I bet it does).

If you haven’t read Why We Get Fat, do so now, I can’t recommend it highly enough.