A new study presented at NUTRITION 2026 suggests that prebiotic sodas often contain more sugar and calories than diet sodas and flavored sparkling waters.

A study presented at the NUTRITION 2026 conference in Washington, D.C., indicates that prebiotic sodas may contain more sugar and calories than manufacturers claim. Researchers analyzed 108 prebiotic sodas launched in the United States between 2021 and 2025, finding that these beverages often contain more sugar and calories than diet sodas or flavored sparkling water. The study has not yet been published in a peer-reviewed journal.

Nutritional Content and Fiber Variability

The research found that the fiber content in prebiotic sodas varies significantly, ranging from approximately 2 to 9 grams per can. Lead study author Carlos R. Soto Díaz noted that because of this wide range, consumers should verify the nutrition facts label rather than relying solely on marketing terms like 'prebiotic.' While prebiotics are fibers that can support gut health, experts caution that these sodas are not equivalent to a high-fiber diet. Registered dietitian Monique Richard and gastroenterologist Dr. Rudolph Bedford noted that while these products are not a scam, they may be marketed in ways that exaggerate their health benefits compared to whole-food sources of fiber.

Impact on Dietary Choices

The study suggests that while prebiotic sodas might reduce calorie and sugar intake when replacing regular soda or fruit drinks, they may increase intake when substituted for diet soda or flavored sparkling water. Experts emphasize that supporting the gut microbiome is best achieved through a consistent, diverse diet of fiber-rich whole foods, such as vegetables, fruits, and grains, rather than relying on isolated fibers added to beverages.