Does Celsius Break a Fast?

If you’re intermittent fasting and need to know if drinking Celsius will break your fast, then you’ll find everything you need to know here.

Intermittent fasting can be a very effective dieting method for weight loss along with health benefits like improved insulin sensitivity and anti-aging. Wouldn’t it be nice to be able to drink a Celsius when fasting to get an energy boost without breaking your fast?

It can be confusing knowing exactly what you can’t and can’t drink during intermittent fasting that won’t cause you to break your fast. The last thing you want to do is unknowingly break your fast by drinking the wrong thing and ruining your results.

Here, you’ll discover why Celsius can break your fast… and why it can’t. I’ll break down the ingredients in Celsius energy drinks and how they interact with your body when fasting.

Can You Drink Celsius Energy Drink When Fasting?

celsius energy drinks on grocery store shelf

So does Celsius break a fast?

Quick Answer: Drinking a Celsius energy WON’T break your fast, especially if your main goal with intermittent fasting is weight loss. The best choices of Celsius are their original Celsius Essential Energy, Celsius HEAT, and Celsius BCAA +Energy.

Celsius is a popular energy drink that can also be used as a pre-workout for an energy boost. They contain a tiny amount of calories per can, which makes some believe it could cause it to break your fast.

A can of Celsius contains 10 calories and 2g of carbs. So if you’re following a strict and 100% pure water fast, then a Celsius will break your fast (as well as anything other than water).

But if weight loss is your primary goal with intermittent fasting, then you’re in luck. Fasting isn’t like an on/off light switch, and there is some gray area for wiggle room.

A “50-calorie rule” allows less than 50 calories during your fasting window as long as it isn’t sugar. So, for example, if you want to add a dollop of half and half to your morning coffee, then you don’t have to worry about all your fasting benefits going out the window.

So, by that fasting rule, you can still have Celsius during your fasting period without it breaking your fast.

And if it helps curb hunger and give you an energy boost, it could make it easier to keep fasting for longer. This will make it easier to stick to your fasting period and get more results in the long run.

Is Celsius Healthy or Bad for You (Side Effects)

Celsius contains some healthy ingredients, but it’s also not the best thing in the world to have every day.

Sucralose is an artificial sweetener in Celsius, which could harm your gut and brain health. Studies have found those consuming artificial sweeteners can end up gaining weight.1

Some believe that since sucralose is so sweet, it could cause an insulin spike despite it having zero calories. Sucralose is 600 times sweeter than regular sugar, so some believe it could cause your body to release insulin in anticipation of incoming sugar and calories. This is called cephalic phase insulin release.2

Since sucralose is so sweet, it could cause you to gain a preference for sweeter foods. This could possibly lead to you overeating sugar and refined carbs later in the day.3

But it’s better to have an energy drink made from artificial sweeteners with near-zero calories than one from regular sugar.

There aren’t any long-term studies finding any severe side effects, and as long as you’re limiting your intake the rest of the day, you should be okay.

Does Celsius Spike Insulin?

The theory that your body releases insulin because sucralose is so much sweeter than sugar only makes sense if your body is a “sugar burner.” Sugar burner’s bodies rely on recently eaten sugars and carbs for fuel instead of body fat.

As you start fasting more and reducing your sugar and carb intake, you’ll become more fat-adapted. This means your body will have an easier time burning fat for fuel instead of relying on sugar and carbs.

So by drinking Celsius when fasting, your body should become used to it, not receiving incoming sugars or calories despite the sweetness of sucralose. Fatigue when starting an intermittent fasting program can happen when your body is making this sugar-to-fat-burning adaptation.4

Does Celsius Break Ketosis?

Celsius only contains 2g of carbohydrates and zero grams of sugar, so it shouldn’t break ketosis. It’s recommended to keep your daily total carb intake below 30 grams so as not to disrupt ketosis.

Ketosis is a metabolic state that occurs when your body switches from using glucose as its primary energy source to using fat as its primary fuel source. When your body is in a state of ketosis, it produces ketones, molecules produced in the liver from fatty acids and used by other tissues for energy. 

The 2g of carbohydrates could possibly stop ketosis if your body isn’t ready to burn fat for energy yet. But a small amount of carbs from Celsius won’t cause a problem as long as you’re sticking to your intermittent fasting program and limiting your overall carb intake.

Does Celsius Burn Fat?

Energy drinks like Celsius also contain caffeine that boosts your metabolism, helping you burn more calories and fat. There are 200mg of caffeine in Celsius energy drinks, making them on the higher end of caffeine content.

Caffeine stimulates thermogenesis, which speeds up your metabolism by generating body heat.5 Your nervous system is also stimulated by caffeine, which tells your fat cells to break down fat.6 Caffeine can also curb hunger by suppressing your appetite, making it easier to keep fasting for longer.7

Celsius also contains ingredients like taurine, guarana extract, ginger extract, and green tea extract that have health benefits.

Taurine: Taurine is a type of acid that helps build protein. Studies on animals have shown that taking taurine can help reduce weight and fat.8 It does this by helping your body use fats better, reducing inflammation and stress, which can lead to gaining more weight. Taking a combination of taurine, caffeine, and green tea extract may also help your body burn more fat during exercise.

Guarana extract: Guarana extract is the caffeine source in Celsius energy drinks. Caffeine can help boost metabolism, enhance physical performance, burn more fat, and curb hunger.9

Ginger extract: Ginger also helps to increase thermogenesis, heating up your body, which causes it to use more energy and burn more fat.10 Ginger enhances the thermic effect of food and promotes feeling full, helping to curb hunger.11

Green tea extract: A well-known fat burner due to its catechins content, antioxidants that boost metabolism. Research has found green tea extract can help burn more fat and improve insulin sensitivity.12,13

Why Zero Sugar Energy Drinks Don’t Break a Fast

The good news is you can drink energy drinks without breaking your fast. Zero-sugar energy drinks are a must, so check the nutrition facts before drinking during a fast.

As long as you’re not following a strict water fast, you’ll be fine having a zero-sugar energy drink when intermittent fasting. While it’s believed by some that the artificial sweeteners in zero-sugar energy drinks could cause an insulin reaction, this hasn’t been proven.

This will depend on how well your body has become fat-adapted. If it’s still a “sugar burner,” then you could quickly expect your body to release insulin after drinking an energy drink despite it containing no sugar. But your body should adjust gradually to be fat-adapted, and this insulin reaction should be less prevalent.

If your main goal with intermittent fasting is to lose weight, then zero-sugar energy drinks are acceptable. Especially if they give you an energy boost, make fasting easier, and curb hunger. You’ll win out in the long run by fasting longer by having an energy drink instead of giving in to the hunger pangs.

But you also should expect less than 100% maximum of the benefits from intermittent fasting. Consumption of energy drinks will limit or nonexistent Autophagy and gut health improvements. Ideally, you’d have a continuous glucose monitor to track your blood sugar response from the energy drink.

Water, coffee, unsweetened teas, sparkling water, and even energy drinks won’t break a fast as long as they don’t have any added sugar. When fasting, try adding C8-MCT keto coffee creamer to your morning coffee to flip the “metabolic switch” and start burning more body fat for fuel.14 They won’t break your fast but will give you an energy boost, more mental clarity, and curb hunger.

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So does Celsius break a fast? Celsius can be a useful drink to help you fast for longer periods of time. It doesn’t contain any sugar and only 2g of carbohydrates, so it won’t break ketosis or cause an insulin spike if your body is already fat-adapted.

Celsius energy drinks, often used for their energy boost, fall into this gray area. While a can of Celsius contains 10 calories and 2g of carbs, which could technically break a strict water fast, it adheres to the “50-calorie rule,” which permits the intake of fewer than 50 calories as long as it isn’t sugar. 

The caffeine and other ingredients in Celsius, like taurine, guarana extract, ginger extract, and green tea extract, will help boost metabolism as well as provide energy without breaking the fast.

If your primary goal is weight loss, a Celsius drink won’t disrupt your fast and might even assist by curbing hunger and providing energy, making it easier to keep going with the fast.