Do Seltzers Have Aspartame? Unveiling Sweetener Secrets

December 1, 2025 •

3 min read

Approximately 77% of U.S. adults consume carbonated beverages. Not all seltzers contain aspartame; it depends on the product. Plain seltzer typically avoids sweeteners, while flavored or diet versions might use artificial options like aspartame for a sweet taste without the sugar or calories.

Quick Summary

Seltzers may or may not contain aspartame. To know for sure, check the ingredient list. Artificial sweeteners such as aspartame are common in flavored and diet seltzers, but many brands use natural alternatives.

Key Points

Plain vs. Flavored: Plain seltzer has no sweeteners; flavored and diet versions might have aspartame.
Check Labels: Look for "aspartame" or "E951" on ingredient lists to identify aspartame.
Natural Options: Many brands are using natural sweeteners like stevia and monk fruit.
Phenylketonuria Warning: Products with aspartame must have a warning for people with PKU.
Hard Seltzer Variations: Some hard seltzers use natural flavors, but others, particularly diet ones, may have artificial sweeteners.
Consumer Preference: Natural sweeteners reflect consumer demand for cleaner ingredients.

The prevalence of aspartame in seltzers is a common concern for those watching their sugar and calorie intake. The answer to "do seltzers have aspartame?" isn't straightforward. Plain sparkling water consists of just carbonated water and thus contains no added sweeteners. However, flavored and diet seltzers frequently contain sweeteners to achieve their taste profiles.

Sweeteners in Seltzer: A Closer Look

Artificial sweeteners like aspartame, acesulfame potassium (Ace-K), and sucralose have long been used to reduce the calorie count in beverages. As consumer preferences evolve, many seltzer brands are moving toward natural sweeteners to meet the demand for cleaner labels.

Types of Sweeteners in Seltzer

Natural Flavoring: Many brands use natural essences from real fruits. These typically contain no added sugars or sweeteners.
Stevia: This is a plant-based, zero-calorie sweetener extracted from the stevia plant.
Monk Fruit: A natural, zero-calorie sweetener derived from monk fruit.
Erythritol: This sugar alcohol occurs naturally in some fruits and fermented foods. It's often used with other sweeteners.
Aspartame (and others): Artificial sweeteners such as aspartame (Equal, NutraSweet), sucralose (Splenda), and Ace-K remain common in many "diet" or "zero-sugar" products.

Artificial vs. Natural Sweeteners in Seltzer

Comparing seltzers with artificial sweeteners like aspartame to those with natural alternatives involves considering their origins and possible health effects. While both offer a sweet taste without calories, their sources and potential impacts vary.

Seltzer Sweetener Comparison


Feature	Artificial Sweeteners (e.g., Aspartame)	Natural Sweeteners (e.g., Stevia, Monk Fruit)
Source	Chemically synthesized	Extracted from plants or fruits
Caloric Content	Virtually zero	Virtually zero
Labeling	Labeled as "aspartame" or "E951"	Often listed as "natural flavors" or by name
PKU Warning	Requires phenylalanine warning	No warning needed
Consumer Perception	Avoided by some	Considered a "cleaner" option
Taste Profile	May have an aftertaste	More rounded flavor profile

Identifying Aspartame in Seltzers

To know if your seltzer contains aspartame, examine the ingredients list. Aspartame is listed by name or the code E951. Additionally, products with aspartame must include a warning for those with phenylketonuria (PKU), indicating the presence of phenylalanine. A can of Diet Coke lists aspartame, while a can of Bubly Sparkling Water does not.

Aspartame in Hard Seltzers

The ingredient list for hard seltzers, which are alcoholic, can differ. While early hard seltzers relied on fermented sugar, many now use other methods. Brands like White Claw and Truly often use fermented cane sugar with natural fruit flavors, without aspartame. However, some alcoholic seltzers, especially lower-carb or diet options, might still use artificial sweeteners. Always check the label for each brand and flavor.

Conclusion

In summary, plain seltzer water avoids aspartame, but flavored and diet varieties might contain it. The trend in the beverage industry is to move towards natural sweeteners. Always check the ingredients and the phenylalanine warning. Many naturally sweetened or unsweetened seltzer options exist for consumers who prefer to avoid artificial additives. Reading ingredient lists is key to knowing what is in your drink.

World Cancer Research Fund provides more about sweeteners and cancer risk, including the IARC's classification of aspartame.

Frequently Asked Questions

Plain seltzer has no sweeteners. Flavored and diet seltzers might contain aspartame, sucralose, or acesulfame potassium, as well as natural sweeteners like stevia, monk fruit, or erythritol.

Check the ingredient list on the label. Aspartame is listed by name or as E951. Many brands also advertise if they use natural sweeteners.

No, many brands now use other sweeteners, such as stevia or monk fruit, or natural fruit essences without sweeteners.

Diet seltzers are often more likely to contain aspartame. Hard seltzers vary, with some using fermented sugar and natural flavors, while others might use artificial additives.

White Claw and Truly generally do not use aspartame. They typically derive their alcohol from fermented cane sugar and use natural fruit flavors.

The safety of sweeteners is debated and depends on individual health. Many consumers prefer natural options for personal reasons.

Products with aspartame must state that they contain phenylalanine. This is crucial for people with phenylketonuria (PKU), who cannot process phenylalanine.