Intermittent Fasting Stages And What You Should Expect [Hour-By-Hour]

Updated: Jan 20

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If you're new to Intermittent Fasting, you're probably wondering what you should actually expect, hour-by-hour, with Intermittent Fasting. In other words, what are the Intermittent Fasting stages? When do you burn fat, when should you eat, when should you stop?

Today, I'm breaking down the details of what's happening in the body at each Intermittent Fasting stage and what you can expect.

What Are The Stages Of Intermittent Fasting?

Intermittent Fasting is broken down by whether or not you're eating. When looked at with this perspective, Intermittent Fasting can really be broken down into just two stages: fasting and feeding. But in order to understand exactly what's happening while you're using Intermittent Fasting for the first time, I've broken down the first 48 hours of Intermittent Fasting into 5 stages.

Related: How Long Does It Take For Intermittent Fasting To Work?

Intermittent Fasting Stages

Stage 1: 0-12 Hours (Fasting)

The first stage of Intermittent Fasting is your first eating window. This begins with the last bite of food that you took the night before. For example, if you stopped eating at 7pm on Friday, your first 12 hours of fasting will take you to 7am Saturday morning. As you can probably see, for most people, this first 12 hours of fasting might not be too different from your current routine. Around 8 hours of your first fasting window is when you're sleeping, so this first 12 hour fasting period should be fairly simple. Not to mention, naturally higher levels of cortisol (our stress hormone) in the morning helps to increase energy levels without needing to eat breakfast right away.(1)

However, the real perks of Intermittent Fasting begin after you have fasted for 12 hours. This is where stage 2 of Intermittent Fasting begins...

Pssst - wondering what type of fasting is best for your goals? Click below for my free Intermittent Fasting Schedule quiz to find out!

Related: [QUIZ!] Find Out The BEST Intermittent Fasting Schedule For YOUR Goals!

Intermittent Fasting Stages

Stage 2: 12-16 (Fasting)

Around 12 hours of fasting is when your body starts to ramp up fat burning. Anytime <