Prebiotic sodas have become a popular option for people who want something sweeter than sparkling water but lighter than regular soda. New research suggests that these drinks often do occupy a nutritional middle ground, though their gut-health image may promise more than their labels can prove.
In a preliminary analysis of products introduced in the U.S. between 2021 and 2025, researchers found that prebiotic sodas generally contained fewer calories and less sugar than regular sodas and fruit drinks. At the same time, they contained more calories and sugar than diet sodas and flavored sparkling waters.
The study was presented at NUTRITION 2026, the annual meeting of the American Society for Nutrition, and has not yet undergone the full peer review required for publication in a scientific journal. It examined product labels and nutrition data, not whether drinking prebiotic soda improves digestion, changes the gut microbiome or leads to better health.
Researchers from the University of North Carolina at Chapel Hill analyzed 3,709 ready-to-drink beverages listed in the Mintel Global New Products Database. The sample included 108 prebiotic sodas, which were defined as carbonated drinks containing fiber and using the term “prebiotic” in the product name, claims or ingredient information.
They compared the drinks with regular soda, diet soda, fruit drinks and flavored sparkling water.
The typical prebiotic soda contained about 35 calories, 5 grams of sugar and 5 grams of fiber per 12-ounce can, according to the news release. Individual products varied, with fiber ranging from about 2 to 9 grams per can.
Compared with regular sodas and fruit drinks, prebiotic sodas contained less total sugar, less added sugar and fewer calories. They also contained more fiber than every other beverage category included in the analysis.
But the comparison looked different when prebiotic sodas were measured against diet soda or flavored sparkling water. Those options generally had fewer calories and less sugar, though they also contained less fiber.
That makes the question of whether prebiotic soda is a better choice largely dependent on what someone would otherwise drink.
For a person who regularly drinks full-sugar soda or fruit drinks, switching to a prebiotic soda could reduce sugar and calorie intake while adding some fiber. For someone who already drinks water, unsweetened sparkling water or another low-calorie beverage, the nutritional advantage may be smaller.
“Many products include nutrition and functional claims that may overstate their nutritional quality,” said Carlos R. Soto Díaz, a doctoral student at the University of North Carolina at Chapel Hill and the study’s presenting author.
One example is the phrase “no added sugar.” A drink with no added sugar may still contain naturally occurring sugar from juice or another ingredient. That does not necessarily make the claim inaccurate, but it means “no added sugar” should not be read as “sugar-free.”
The researchers also found that nearly 65% of prebiotic sodas contained non-nutritive sweeteners, such as stevia. That was less common than in diet sodas but more common than in regular sodas, fruit drinks and flavored sparkling waters.
The study did not evaluate whether those sweeteners were beneficial or harmful. Their presence may simply matter to consumers who prefer or avoid certain ingredients.
The word “prebiotic” also does not guarantee a particular amount of fiber. Unlike some regulated nutrient claims, the term is not tied to a standard fiber level in the U.S. A drink can use prebiotic fiber and still contain only a modest amount per serving.
Prebiotic fibers are ingredients that can be used by certain gut microbes. Some types have been studied for possible effects on digestion and gut health, but benefits can depend on the specific fiber, the dose and the person consuming it.
This analysis could not determine whether the amounts in these beverages were enough to produce a meaningful effect.
“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 Díaz said.
The study also did not examine how often people drink the products, what they eat alongside them or whether prebiotic sodas improve overall diet quality. It only compared the nutritional profiles of products as listed in a commercial database.
That makes the Nutrition Facts label more useful than the front-of-package language alone. Consumers can compare total sugar, added sugar, calories, fiber and sweetener ingredients rather than assuming every drink marketed as prebiotic has the same profile.
The findings do not suggest that prebiotic sodas are equivalent to regular soda, nor do they establish them as an important source of fiber. Instead, they show that these drinks sit somewhere between sugary beverages and low- or no-calorie alternatives.
For many people, the most useful question may not be whether prebiotic soda is healthy in the abstract. It’s whether that particular drink fits their needs better than the beverage it’s replacing.
The research was supported by an NIH training grant and Bloomberg Philanthropies.