Prebiotic Sodas Show Varied Fiber and Sugar Content
Prebiotic sodas have gained popularity in recent years, largely due to their purported gut health benefits and low-calorie appeal. However, a new study led by Carlos R. Soto Díaz, a PhD candidate at the University of North Carolina at Chapel Hill, suggests that these beverages may not always meet their advertised nutritional standards. The analysis, which will be presented at NUTRITION 2026, the annual meeting of the American Society for Nutrition, found that many prebiotic sodas contain less prebiotic fiber and more sugar than consumers might expect based on marketing claims.
The study examined 108 prebiotic sodas launched in the U.S. between 2021 and 2025, using data from the Mintel Global New Products Database. These sodas, defined as carbonated beverages containing fiber and labeled as prebiotic, were compared to regular sodas, diet sodas, fruit drinks, and flavored sparkling waters introduced during the same period. On average, prebiotic sodas were found to contain about 35 calories, 5 grams of sugar, and 5 grams of fiber per 12-ounce can.
While prebiotic sodas contained more fiber than other beverage categories, ranging from about 2 to 9 grams per can, the term "prebiotic" is not associated with a specific fiber amount in the U.S. market. Researchers caution consumers against assuming that these beverages are a significant source of dietary fiber. In terms of sugar content, some products marketed as having 'no added sugar' still contained around 10 grams of total sugars, often derived from juice.
In comparison to other beverages, prebiotic sodas ranked lower in calories and sugar than regular sodas and fruit drinks but higher than diet sodas and flavored sparkling waters. The study also noted that nearly two-thirds of prebiotic sodas contained non-nutritive sweeteners like stevia, compared to over 90% of diet sodas, 28% of fruit drinks, 16% of flavored sparkling waters, and 12% of regular sodas.
Reflecting on these findings, Soto Díaz advised consumers to critically evaluate nutrition labels rather than rely on marketing claims. He emphasized that while certain prebiotic fibers can support gut health, the amounts in these sodas may not offer significant benefits. Instead, any potential health advantages should be considered alongside the product's complete nutritional profile, including calories, sugars, and sweeteners.
The study highlights the importance of understanding what prebiotic sodas might replace in a diet. For those who frequently consume sugary drinks, switching to prebiotic sodas could reduce calorie and sugar intake. However, for individuals who usually opt for low- or no-calorie beverages, the benefits may be less pronounced.
