What Are the “Natural Flavors” in Your Can of Seltzer?

Flavored seltzers have exploded in popularity over the past decade, offering a bubbly, calorie-free alternative to sugary sodas and juices. Marketed as refreshing and healthy, many of these beverages list “natural flavors” or “natural ingredients” on their labels.

What does that actually mean? You’d be forgiven for having no clue. Though “natural flavor” is the fourth most common ingredient listed on ingredient labels, according to the Environmental Working Group‘s Food Scores database of over 80,000 foods, seltzer companies tend to keep the specifics of their production processes under lock and key.

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What are “natural” flavors?

In short, “natural ingredients” in flavored seltzers usually refer to natural flavors, a term regulated by the U.S. Food & Drug Administration (FDA).

According to the FDA, a natural flavor must originate from a plant or animal source—such as fruit, herbs, spices, bark, roots, or other natural materials. However, the term can be misleading, as it doesn’t necessarily mean that the flavor comes directly from the fruit pictured on the can.

For example, a “natural raspberry flavor” in a seltzer might not come from actual raspberries but instead from flavor compounds derived from other natural sources that mimic the taste of raspberry. These compounds are typically extracted using solvents or fermentation processes in a lab setting. While the final product is chemically identical to the flavor found in nature, it may have never been in contact with the real fruit.

According to research by The Wall Street Journal, flavor “essence” found in seltzer could undergo the same process as essence found in shampoo or other scented products. Tasting Table notes that this is done by “taking the skin of a fruit, for example, and heating it to produce vapors that are then infused into the beverage.”

In addition to flavor compounds, these natural flavor formulations can also contain solvents, preservatives, or emulsifiers—all derived from natural sources—to help stabilize and preserve the flavor. However, companies aren’t required to disclose the specific ingredients used in their natural flavor blends, as they’re considered proprietary.

“Natural and artificial flavors play an interesting role in food. They’re essentially providing the taste and often they’re added to make the food more appealing, or to potentially replace something that’s lost through processing, storage or in some cases even from pasteurizing,” David Andrews, PhdD, senior scientist at the Environmental Working Group, recently told CNN Health.

“The differentiation [between natural and artificial flavors] is really down to the origin of those molecules, whether synthetically processed in a lab or purified in a lab but from a natural source,” Andrews added.

In natural flavors, “The mixture will often have some solvent and preservatives—and that makes up 80 to 90 percent of the volume [of the flavoring]. In the end product, it’s a small amount, but it still has artificial ingredients,” Andrews told the outlet.

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Nutrition content creator Kyle Fitzgerald, best known for his brand Clean Kitchen Nutrition,  recently shared that these products can contain up to 100 added chemicals that do not need to be disclosed on the ingredients list, since they’re considered proprietary property. He recommends skipping any seltzer products that contain “natural flavors” in favor of those featuring citrus or fruit, such as Spindrift or Sanzo.

So, while “natural ingredients” sounds wholesome, the term is more about regulatory classification than farm-to-bottle purity. These flavors are safe and widely used, but if you’re seeking a truly fruit-derived beverage, look for drinks labeled with actual juice content or whole fruit infusions.