Does a Protein Shake Break a Fast? [Intermittent Fasting Tips]

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Will a protein shake break your fast? Or can you sip on a protein shake throughout your Intermittent Fast and still burn fat?


Today, we're breaking down exactly what you need to know about protein shakes and Intermittent Fasting.


does a protein shake break a fast

Does a Protein Shake Break a Fast?

A protein shake will typically contain pure protein. Sometimes you'll also find some sugar or fat added in. However, let's assume your protein shake is a pure protein without added sugar or fat. Will your protein shake break a fast?


Whether or not something breaks a fast comes down to if it causes the body to release the storing hormone insulin. The main fat burning, weight loss and wellness perks of Intermittent Fasting come from the fact that you're not releasing insulin while you're fasting. So if you start releasing insulin in response to something you consume during the fast, you're no longer receiving the health and weight loss perks and have therefore broken your fast.


Insulin is primarily released when we eat food. Carbohydrates cause the biggest release and protein causes a relatively smaller release. This means if you consume protein or carbohydrates during your fast, you will break your fast. On the other hand, fat has zero impact on insulin. This is why some fats in your coffee (like with the Keto Coffee recipe) can be consumed during the fast without breaking your fast.


Considering a protein shake is a pure protein source, it will break a fast. Not to mention if it has any sugar added in, it will cause an even bigger insulin spike.


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!


does a protein shake break a fast


The Best Protein Shakes For Intermittent Fasting

However, this doesn't mean that you want to cut your protein shake out of your Intermittent Fasting routine - you just wan to have it at the right time: when you break your fast. Consuming enough protein from complete protein sources is crucial for achieving a body recomposition goal where you're losing body fat while maintaining muscle mass.


Pairing your protein with high quality fats is even more important if you're also working out while Intermittent Fasting. One study found that protein plus fat was better at helping the muscles recover from a workout than just protein alone.(1)


Checkout 5 of my favorite high quality protein, fat and fiber protein shakes below. Break your next Intermittent Fast with these!


will a protein shake break a fast

Vanilla Peanut Butter Smoothie

This smoothie is packed with high quality protein to help repair your muscles post workout and keep you satisfied during your next fasting window.