How does low carb work?

The simple version of low carb is:

carbs -> increase insulin -> increase fat storage

Low-carbing is a way of eating which reverses this bodily process.

The great indoor sport

What insulin does is not controversial at all.

In every endocrinology textbook since the discovery of insulin in 1921, it is simply stated that insulin is the hormone that sweeps blood sugar into our fat cells and makes them bigger.

When we eat carbohydrates, they turn to blood sugar. Fat does not do this. Protein gets skimmed off for body repair and other processes, and can, at the end of a long process, become small amounts of glucose released as needed.

So when we want to flood the body with insulin, we eat processed carbs. They fall into the bloodstream like a cascade of sugar... which is what they are.

"Starch" is just a name for sugar that isn't sweet. "Fiber" is the parts taken out during processing, that does slow down the process. But most of what we eat in what is considered a "normal diet" is a small amount of actual food surrounded by sugar and starch and other substances that drive up blood sugar.

What goes up must come down. Past a certain point, blood sugar is a poison. This is how poorly controlled diabetics start having breakdowns in every single system in their bodies. Insulin is the response to a blood sugar emergency.

Where does the blood sugar go? Into our fat cells.

The higher the blood sugar, the more fat gets ushered into our fat cells and then locked down tight; because as long as insulin circulates, fat can't get out.