Allulose vs Sucralose vs Aspartame: Which Is Best for Sugar-Free Hydration?

What's Actually Sweetening Your Sugar-Free Drink

Flip a sugar-free hydration drink over to read the label and the sweetener is usually one of three ingredients: allulose, sucralose, or aspartame. It's an easy line to skim past, but that ingredient shapes how close it tastes to the real thing.

The distinction worth paying closest attention to is whether the sweetness comes from something that occurs in nature or something made in a lab. Allulose is a naturally occurring sweetener, while sucralose and aspartame are both artificial sweeteners. The differences are worth understanding before you commit to a sweetener you'll reach for every day.

Keep reading to learn about each sweetener so the next time you shop, you can line them up and understand what's in your drink of choice — and which one fits your hydration needs.

What Allulose Is (And Why It Acts Like Sugar Without Being Sugar)

Allulose is a rare, naturally occurring sweetener found in small amounts in foods like figs, raisins, wheat, and corn. It's technically a carbohydrate, and it tastes and textures remarkably like table sugar because its molecular formula is the same as fructose. The difference is in how your body handles it.

Unlike regular sugar, allulose passes through the digestive system largely intact and is excreted rather than used for energy. The result is a sweetener that delivers about 10% the calories of sugar,1 has minimal impact on blood glucose,2,4 offers good digestive tolerance,3 and is suitable for keto-friendly and low-carb diets. It's also hydration for your GLP-1 journey.*

Put simply, allulose behaves like sugar on your tongue without carrying sugar's metabolic impact. That's a genuinely different category from the artificial options like sucralose or aspartame.

*Liquid I.V. helps with hydration but is not intended to treat or prevent any disease. Please consult your doctor if you are considering using Liquid I.V. along with GLP-1

What Sucralose and Aspartame Are

Sucralose and aspartame are artificial, lab-made sweeteners used widely across zero-sugar diet beverages. Both are high-intensity sweeteners, meaning they're hundreds of times sweeter than sugar and used in very small amounts to reach the same level of sweetness. Some people notice a slight aftertaste with each — that's a taste observation, not a comment on safety.

The point here isn't to rank them as good or bad. It's the category line: sucralose and aspartame are made in a lab, while allulose occurs in nature. That single distinction is what leads into the comparison below.

Allulose vs Sucralose vs Aspartame: The Side-by-Side

Here's how the three sweeteners stack up on the things shoppers actually care about:

The right-hand column is the one to sit with. Allulose is the only sweetener of the three that Liquid I.V.® uses, and only in its Sugar-Free lines. Liquid I.V. never uses sucralose or aspartame.

Is Allulose Safe? What the FDA Says

It's a common question about sweeteners, so let's answer it plainly. Allulose is approved for use in the U.S. by the FDA.1 Because of how the body processes it — passing through without being metabolized — current regulations also allow it to be excluded from total and added sugars lines on the Nutrition Facts label.1

Allulose also tends to be gentle on digestion. The takeaway: allulose is an FDA-recognized, naturally occurring sweetener, not an experimental ingredient.

Does Allulose Cause Bloating or Stomach Issues?

This is the single biggest hesitation people have about allulose, so here's the honest answer. Allulose is a rare sugar found naturally in foods like figs, raisins, and wheat — and importantly, it is not a sugar alcohol. Sugar alcohols like xylitol, mannitol, erythritol and sorbitol are the sweetener category most often associated with bloating and gas. Allulose is a different category entirely.

Allulose has good digestive tolerance, and Liquid I.V. Sugar-Free uses it in measured, single-serving amounts. Published clinical research found allulose well-tolerated even at up to three sticks of an allulose-containing hydration beverage per day for four weeks, with participants reporting no major gastrointestinal distress.3

As with any food, individual tolerance varies, so it's worth sticking to the recommended serving. But you can feel confident knowing allulose lives outside the sugar-alcohol category most linked to GI discomfort.

How to Tell What Sweetener Your Hydration Drink Uses (and Which to Pick)

Turning this into a decision is straightforward once you know what to look for:

• Check the ingredient line: Sweeteners are listed by name — allulose, stevia, sucralose, aspartame, acesulfame potassium, erythritol.

• Naturally occurring vs. artificial: Allulose and stevia are naturally occurring; sucralose, aspartame, and acesulfame potassium are artificial; erythritol is a sugar alcohol.

• Blood-sugar priority: Allulose has minimal impact on blood sugar, which matters for keto-friendly, low-calorie, and blood-sugar-conscious shoppers.

• Taste priority: Allulose tastes closest to sugar.

• What Liquid I.V. uses: Sugar-Free is built on allulose, plus a small amount of stevia leaf extract for taste.

Most sugar-free hydration drinks lean on one or more artificial sweeteners. If you specifically want a naturally occurring sweetener that performs like sugar, Hydration Multiplier® Sugar-Free should be top of your list.

How to Choose the Sweetener That Works Like Sugar Without the Downsides

You can now tell allulose, sucralose, and aspartame apart, name which are naturally occurring, and read a label with confidence. To recap the spine of it: allulose is the naturally occurring option that tastes like sugar, carries about 10% of sugar's calories,1 and does not raise blood sugar levels,4 — and it's the sweetener Liquid I.V. Sugar-Free is built on.

If that's the profile you're after, it's worth exploring the Hydration Multiplier® Sugar-Free collection.

Frequently Asked Questions

Is allulose natural or artificial? Allulose is a naturally occurring sweetener, found in small amounts in foods like figs, raisins, wheat, and corn.

Does allulose raise blood sugar? No. Allulose does not raise blood glucose levels,2,4 which is part of what sets it apart from regular sugar.

Does allulose cause bloating or stomach issues? Allulose is a rare natural sweetener, not a sugar alcohol — and sugar alcohols like erythritol and sorbitol are the category most associated with bloating and gas. Allulose has good digestive tolerance and was well-tolerated in published research3 even at up to three sticks of an allulose-containing hydration beverage per day for four weeks, with no major GI distress. Individual tolerance varies, so follow the recommended serving.

Is allulose better than sucralose or aspartame? That's your call. Allulose is naturally occurring and tastes closest to sugar; sucralose and aspartame are artificial sweeteners. It comes down to what you prioritize on the label.

Is allulose keto-friendly? Yes. With about 10% the calories of sugar1 and becuase it does not raise blood sugar levels,4 it's suitable for keto and low-carb diets.

What sweetener does Hydration Multiplier® Sugar-Free use? The Proprietary Amino Acid Allulose Blend, plus a small amount of stevia leaf extract for taste. No sucralose or aspartame.

Is allulose FDA-approved? Yes — allulose is approved for use in the U.S. by the FDA,1 and current regulations allow it to be excluded from total and added sugars on the Nutrition Facts label.1

Want to taste it for yourself? Explore the Hydration Multiplier® Sugar-Free collection.

This article is for informational and educational purposes only.

References

1.     US Food and Drug Administration. Guidance for Industry: The Declaration of Allulose and Calories from Allulose on Nutrition and Supplement Facts Labels. US Food and Drug Administration; 2020. Accessed July 17, 2026. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/guidance-industry-declaration-allulose-and-calories-allulose-nutrition-and-supplement-facts-labels

2.     Gopalakrishnan ST, Kooima PK, Kavouras IE, et al. Allulose-sweetened beverage maintains glycemic stability during post-exercise rehydration in the heat. J Acad Nutr Diet. 2025;125(10):A70. 

3.     Bloomer RJ, Pence J, Hellenbrand J, et al. Randomized trial to assess the safety and tolerability of daily intake of an allulose amino acid-based hydration beverage in men and women. Nutrients. 2024;16(11):1766. doi:10.3390/nu16111766

4.     Tani Y, Tokuda M, Nishimoto N, Yokoi H, Izumori K. Allulose for the attenuation of postprandial blood glucose levels in healthy humans: a systematic review and meta-analysis. PLoS One. 2023;18(4):e0281150. doi:10.1371/journal.pone.0281150