Intermittent Fasting and Fat Loss

To understand how intermittent fasting leads to fat loss we first need to understand the difference between the fed state and the fasted state.

Your body is in the fed state when it is digesting and absorbing food. Typically, the fed state starts when you begin eating and lasts for three to five hours as your body digests and absorbs the food you just ate. When you are in the fed state, it’s very hard for your body to burn fat because your insulin levels are high.

After that timespan, your body goes into what is known as the post–absorptive state, which is just a fancy way of saying that your body isn’t processing a meal. The post–absorptive state lasts until 8 to 12 hours after your last meal, which is when you enter the fasted state. It is much easier for you body to burn fat in the fasted state because your insulin levels are low.

When you’re in the fasted state your body can burn fat that has been inaccessible during the fed state.

Because we don’t enter the fasted state until 12 hours after our last meal, it’s rare that our bodies are in this fat burning state. This is one of the reasons why many people who start intermittent fasting will lose fat without changing what they eat, how much they eat, or how often they exercise. Fasting puts your body in a fat burning state that you rarely make it to during a normal eating schedule.

by James Clear @jamesclearblog