• Autumn Bates, CCN, MS

Should You ACTUALLY Break Your Fast With A Protein Shake? [Fasting Do's and Don'ts]

Updated: Feb 3

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Should you really break your fast with a protein shake? Or can you have a protein shake while fasting? Today, I'm breaking down the science-backed details of protein shakes, Intermittent Fasting and the best type of protein shake to achieve your weight loss goals with fasting!

But First, Do Protein Shakes Break Your Fast?

Protein shakes at the very least will consist of a protein powder and a liquid base, such as almond milk, dairy or water. One of the main goals with Intermittent Fasting is to not spike insulin, the fat storing hormone, so that the body can naturally turn on fat burning mechanisms and work toward a weight loss goal.(1) With this in mind, anything that will spike insulin will then break your fast. Protein and carbohydrates are the main macronutrients that will spike the storing hormone insulin (although protein to a much lesser degree than carbohydrates). Therefore protein shakes will break a fast.

There are other forms of fasting that only allow for water, unsweetened coffee or tea during your fasted state. However, if your main objective with Intermittent Fasting is weight loss, then you can opt for either the water fast or use non-insulin spiking drinks such as Keto Coffee during your fast.

Related: "Dirty" vs. "Clean" Fasting | Which One Is Better For Weight Loss?

Should You Have A Protein Shake After Fasting?

Protein is one of the most important nutrients to consume after your Intermittent Fast because it significantly boosts satiety, prevents hunger and helps improve body composition and weight loss progress.(2)

However, another very important macronutrient when breaking an Intermittent Fast is fat. High quality fats trigger the body to release the satiety hormone cholecystokinin, or CCK. This can help to significantly reduce hunger and prevent sugar cravings.(3)

A final necessary component is fiber. Fiber acts on the stretch mechanisms in the stomach and lets the brain know that it's full. These three components of protein, fat and fiber are crucial for boosting satiety, preventing hunger and reducing sugar cravings for long term weight loss success.

A standard protein shake with just protein powder is missing out on the other two important ingredients of fat and fiber. So protein powder mixed with water on its own isn't sufficient to break a fast with. However, when combined with fat and fiber sources, protein powder can certainly be used when breaking a fast.

Related: What's Your Best Intermittent Fasting Schedule For Fat Loss?

Best Intermittent Fasting Protein Shake After A Morning Workout

Instead of opting for a protein shake, transforming your protein powder into a highly satiating smoothie that contains protein, fat and fiber is an excellent way to break a fast while working toward a weight loss goal. Plus, the protein in your smoothie will contribute to the amino acids necessary to help repair your muscles after a morning workout.

Easy fiber sources include chia seeds and flax seeds. Fat can also be added in the form of almond butter, peanut butter, coconut flakes and various nuts or seeds. It's important to strike a balance between high quality proteins, fats and fibers when formulating your break-fast smoothie.

You can checkout one of my go-to, break-fast smoothie recipes combining each of these necessary components with the video below!

Jump start your goals with the Complete Intermittent Fasting Program! Get 7 weeks of meal-by-meal planning and the step-by-step details on how to achieve your weight loss and wellness goals!

Head over HERE to get started!

Your Nutritionist,


Autumn Elle Nutrition

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7021351/

2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4892287/

3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3139783/

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This content (on www.autumnellenutrition.com and in marketing emails from Autumn Elle Nutrition) is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of such advice or treatment from a personal physician. All readers/viewers of this content are advised to consult their doctors, nutritionists and/or qualified health professionals regarding specific health questions. Neither Autumn Elle Nutrition nor the publisher of this content takes responsibility for possible health consequences of any person or persons reading or following the information in this educational content. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians before beginning any nutrition, supplement or lifestyle program.

© 2020 by Autumn Bates, CCN

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