Do Artificial Sweeteners Break A Fast?

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If you’ve got a sweet tooth, losing weight and sticking to a diet can prove challenging. Most calorie-restrictive diets suggest sugars of any description should be avoided. But there is a little wiggle room regarding artificial sweeteners and intermittent fasting.

Here’s a look at how you can add sweetness to your fasting times without feeling guilty. If you keep asking “Can I put sweetener in my coffee during intermittent fasting?” and “Do zero-calorie sweeteners break a fast?” find your answers below.

What is intermittent fasting?

To fully understand the relationship between fasting and artificial sweeteners, it’s vital to grasp the basics of intermittent fasting (IF).

Intermittent fasting is a structured eating plan whereby you refrain from consuming calories for an extended period. The fasting times vary according to your circumstances, but for example, if you are on a 16:8 fasting plan, you would fast for 16 hours (known as the fasting window) and consume food for 8 hours. During the 8 hours you eat, a regular balanced diet with some sugar and carbohydrate content can be enjoyed as well as protein and healthy fats. However, during the 16-hour fasting window, you consume only zero-calorie drinks and water.

Can I use zero calorie sweeteners while fasting?

Most will agree that it is best to avoid artificial sweeteners where possible. However, some artificial sweeteners have more calories than others, and a few have minimal or zero caloric content, making it possible to consume these in diet drinks during your fast.

When questioning if a sweetener or any other substance breaks a fast or not, we take 3 criteria into consideration:

• Does it fluctuate your glucose/insulin levels in the body?
• Does it start any digestive process?
• Does it negatively interfere with the autophagy process of fasting?

If any of your answers to these questions is “yes”, then you’re most probably throwing away your efforts of fasting.

Whether you decide to use artificial sweeteners or not in your fasting-friendly beverages, you can use Fasting Kompanion to track your fasting progress. It will also help you time your fasting cycles and stay motivated!

Types of sweeteners

Let’s now look at intermittent fasting and artificial sweeteners and consider the types of sugars and sweeteners available and how they can affect your fasting diet.

Nutritive Sweeteners (Caloric Sweeteners) and Non-Nutritive Sweeteners

Sweeteners tend to fall into two groups, nutritive and non-nutritive:

1.  Nutritive sweeteners are sugars and sweet substitutes that contain calories and boost energy when consumed. Most conventional sweeteners fall into this group, like:

• Table sugar (sucrose),
• Honey,
• Agave,
• Fructose syrup,
• Sugar alcohols like sorbitol, maltitol, and xylitol.

You can take a look at some of the best sugar alternatives that you can use in your recipes and eat when you crave sugar.

The calorie content between the nutritive sweeteners differs; for example, sugar alcohols (usually ending in -ol) contain roughly half the calories of regular sugar. Only erythritol contains 0.2 per gram, around 95% less than table sugar, making it the least caloric in this group and more akin to a non-nutritive sweetener.

Generally, due to the caloric content, nutritive sweeteners are best avoided during your fasting period as they can break your fast.

Plus, if you’re fasting to improve your gut health, sugar alcohols like sorbitol, maltitol, and xylitol feed the bad bacteria in your gut.

2.  Non-nutritive sweeteners, in contrast, contain little or no calorie content. This group typically tastes far sweeter than regular sugar and is sometimes referred to as “high-intensity sweeteners”, as a little goes a long way. The most common non-nutritive sweeteners include:

• Sucralose (Splenda),
• Steviol Glycoside (Stevia),
• Saccharin (Sweet’N Low),
• Aspartame (Equal),
• Acesulfame (Sunett),
• Luo Han Guo Fruit Extract (e.g. Monk Fruit).

In addition, in a similar manner to erythritol, there’s a new FDA-approved sweetener called Allulose that falls between the two categories. This has a slight natural content and is around 70% as sweet as table sugar. Although it is best to avoid sugars and artificial sweeteners altogether during a fast, due to their zero-calorie content, you can technically drink beverages with a non-nutritive sweetener if desired.

What artificial sweeteners will not break fast?

We have established that non-nutritive sweeteners are allowed in moderation. But which artificial sweetener is the best? Here’s a look at three of the most popular sweeteners in the US and Europe and how their use impacts your body and fasting regime.

Does stevia break a fast?

Steviol glycoside (stevia) contains no calories or protein and is not absorbed or digested in the GI tract, meaning it isn’t known to stimulate the gut. Studies have shown that it may even help to regulate blood sugar and insulin levels. It’s an effective sweetener that doesn’t break your fast or inhibit the ability to burn fat or ketosis. The same study also showed that Stevia is unlikely to impact autophagy, so it is perhaps the best option if you are fasting for weight loss or longevity.

Does Splenda break a fast?

Splenda is derived from sucralose. So the answer to the question “Does sucralose break a fast?” is the same as the answer to “Does Splenda break a fast?” Sucralose is calorie-free, so it doesn’t break your fast.

However, like erythritol and maltitol, its chemical structure is different, causing a different response in the body.

Sucralose in small doses has been shown to have no insulin or blood sugar response, but a recent study indicates it does affect the gut. Splenda can also potentially negatively impact glucose metabolism. Although Splenda is unlikely to inhibit autophagy and research is ongoing, you can assume that there may be better artificial sweeteners on the market. So, if you make a comparison between stevia and Splenda, stevia may be a better choice.

Does saccharin break a fast?

Saccharin (known by the name Sweet ‘N Low) has zero calories and minimal impact on blood sugar and insulin levels. This means it doesn’t technically break your fast in the strictest sense of interrupting fat burning or inducing an insulin spike.

But beware that individual sensitivities to artificial sweeteners are important to consider. Some people find saccharin triggers hunger cravings or digestive issues, impacting their fasting experience and goals.

If your primary focus is weight loss, small amounts of saccharin might be acceptable. However, if you prioritize other benefits like autophagy or maximizing ketosis, avoiding Sweet ‘N Low might be preferable.

Does aspartame break a fast?

Aspartame can be found in many zero-calorie soda drinks like coke and beverages, but it is made up of amino acids. Like Splenda, it technically doesn’t break your fast, but regular consumption could stimulate your gut and decrease insulin resistance.

The brand name of aspartame-containing sweetener is called “Equal”. So, if anyone asks “Does Equal break a fast?”, the same answer about aspartame applies. Equal doesn’t technically break your fast, but regular consumption is not a good idea while fasting.

But the most important thing about aspartame is that, as of July 2023, the World Health Organization has declared that aspartame is now in a group that’s labeled as “might cause cancer in humans”!

Can I drink tea with artificial sweetener during intermittent fasting?

To sum up

The bottom line is that some artificial (non-nutritive) sweeteners can be used during your fast, but not all. Stevia, Splenda, Equal, and other zero-calorie sweeteners that don’t trigger an insulin response or change in your blood sugars are OK to use if you need that sweet kick in your coffee or a can of diet soda. But you should remember that most artificial sweeteners are made in a lab, so you may wish to forgo them for other health reasons. Especially Equal’s (Aspartame) negative effects on health are proven by science.

Nutritive sweeteners on the other hand are a big no during the fasted state, and you should consume them in moderation during your eating window, too.

Get the best intermittent fasting app today to start your weight loss journey with Fasting Kompanion!