The Truth About Probiotic Soda — They're Often Overhyped

You're at the grocery store and you opt for one of those cool new aesthetically designed prebiotic soda. Maybe it's instead of your normal Coke. Or maybe you gave up soda long ago, but are now drinking these "better for you" versions gain. Regardless, you feel good about the choice—it says "gut health" right on the label, after all. It maybe even goes as far as to tout "no added sugar."

We hate to burst your bubble, but according to a new analysis, what's on the can of these popular prebiotics sodas doesn't always match what's inside it.

The soda study

You probably don't need us to tell you—I mean, just walk into any grocery store—but these prebiotic sodas are extremely popular.

In fact, market research shows that prebiotic sodas have become one of the fastest-growing beverage segments in the U.S. The account for an estimated $777 million in sales in 2025. That's a lot of soda!

This reflects how much consumer appetite has grown for drinks that promise a functional benefit beyond basic hydration. This is why researchers wanted to investigate whether these sodas actually have the advantages they promise.

What did they include in their "prebiotic soda" list?

The findings were presented at NUTRITION 2026, the annual meeting of the American Society for Nutrition.

Less fiber, more sugar

Here's what the researchers found:

The fiber picture is more complicated.

In the U.S., there's no regulatory definition tying the word "prebiotic" to a specific fiber amount, which means a product can carry that label even if it contains a relatively small dose.

"Many products include nutrition and functional claims that may overstate their nutritional quality," said Carlos R. Soto Díaz, MPH, a PhD candidate who led the research, in a press release. "This raises concerns that such claims may create a 'health halo,' leading consumers to believe the product is healthier than its overall nutritional profile suggests."

A health halo, in other words, is when a a positive-sounding health claim, like "prebiotic," "gut health," or "no added sugar," shapes how healthy we perceive an entire product to be, even when the full picture is more nuanced.

How to actually evaluate a prebiotic soda

The point of this research isn't to tell you that prebiotic sodas are bad for you, because they're not. If you regularly drink sugary sodas or juice, swapping in a prebiotic soda could meaningfully reduce your daily calorie and sugar intake. They might also add a bit of fiber in the process, making it a reasonable trade. But if you're already reaching for sparkling water or other low- or no-calorie drinks, whether switch to a prebiotic is an upgrade is less clear-cut.

"While certain types of prebiotic fibers have been shown to support gut health, the extent to which the amounts found in these beverages provide meaningful benefits is still unclear," Soto-Diaz says. "Any potential benefits should be considered alongside the product's overall nutritional profile, including calories, sugars and non-nutritive sweeteners."

To figure out what you are really getting in your prebiotic soda, the researchers suggest skipping the front-of-package claims and going straight to the Nutrition Facts label to look for these four things:

The takeaway

Prebiotic sodas aren't a scam, but they're not a shortcut to gut health either. The label "prebiotic" has no regulated minimum fiber requirement in the U.S., which means the actual benefit you get varies widely by brand.

The low dose of fiber in these sodas won't negatively affect you, but the finding is a good reminder us that these whole foods are still your best bet to reliably get fiber. If you are having trouble meeting your fiber goals, check out our RD-approved guide to the best fiber supplements.