Creatine’s muscle-building and strength-boosting effects make it a popular supplement among weightlifters. 

However, many gymgoers who enjoy training fasted fret that creatine disrupts their diet.

Specifically, they worry that creatine breaks their fast.

Fortunately, research shows this needn’t be a concern—creatine doesn’t break a fast in most cases.

That said, some supplements that contain creatine may not be suitable for intermittent fasters because they can also contain other ingredients that raise insulin levels and bring you out of a fasted state.

In this article, you’ll learn the science behind creatine and fasting, how to take creatine while fasting to ensure you stay fasted, and more.

Does Creatine Break A Fast?

Being “fasted” refers to a physiological state where your body has finished processing the last food you ate and the amount of the hormone insulin in your blood is at a low, baseline level.

How long it takes to “reach” a fasted state depends on the size and composition of your last meal—large meals containing a mix of macronutrients usually digest over 5 or more hours, while smaller, simpler meals digest more quickly. 

To “break” a fast, you must consume something that causes your body to shift from a fasted state, to a state where it releases insulin. This could be a small snack, a sip of soda, or indeed, a workout supplement containing calories.

So, does creatine break a fast?

According to a study published in the journal Annals of Nutrition & Metabolism, creatine doesn’t significantly affect insulin levels and therefore doesn’t break a fast. This is because breaking a fast requires you to consume calories, carbohydrates, proteins, or fats—none of which are in creatine.

Crucially, this only applies if you take creatine with water.

Taking it with a calorie-rich beverage, such as fruit juice or protein powder, will break your fast, since these drinks increase insulin levels in your body.

Likewise, taking a pre-workout supplement that combines creatine with other calorie-containing ingredients (e.g., sugar, some sweeteners, or carbs) will break your fast, as these components trigger an insulin response.

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Should You Take Creatine on an Empty Stomach?

Some health and fitness “authorities” recommend taking creatine on an empty stomach to “accelerate its absorption” and help you reap its benefits sooner. 

Research tells a different story, though. 

Although it’s fine to take creatine without food, studies show that consuming it with carbohydrates can boost its absorption. This is because the insulin your body releases after you eat carbs helps transport creatine more efficiently into your muscle cells.

Critically, this is only beneficial in the first few weeks of creatine supplementation. 

Taking creatine with carbs during this period helps to “saturate” your muscles with creatine more quickly, so you’ll experience its benefits sooner.

For long-term creatine users, the situation changes. After the first few weeks of consistent use, your muscles reach “peak creatine levels,” and how or when you take it beyond this point becomes less important. 

At this stage, the key is to consistently take a daily maintenance dose to top off your creatine levels.

How to Take Creatine While Fasting

If you take your creatine supplement during your fasting window and want to avoid breaking your fast, take creatine mixed with water and nothing else. 

To maximize the benefits of creatine while fasting, take 3-to-5 grams per day at whatever time works best for you.

When you start taking creatine, you can “load” it by taking 20 grams daily for the first 5-to-7 days (followed by the “maintenance” dose of 3-to-5 grams daily).

You don’t have to start with a loading phase, but studies show that it causes the creatine to accumulate in your muscles faster, helping you experience its effects sooner.

Benefits of Creatine

Creatine benefits physical performance in multiple ways. Specifically, creatine:

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FAQ #1: Does creatine break ketosis?

No, creatine contains no carbohydrates so it won’t break ketosis. 

FAQ #2: Does creatine spike insulin?

No, research shows that creatine has little effect on insulin levels, hence why it doesn’t break a fast.

FAQ #3: Can I take creatine while water fasting?

Yes, you can take creatine while water fasting. Creatine doesn’t contain calories and, when mixed with only water, doesn’t elicit an insulin response, so it doesn’t break the fasted state.

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