A recent randomized, double-blind, placebo-controlled study was conducted to evaluate the impact of Nutriose, a soluble dietary fiber supplement by Roquette, on the gut microbiota of 124 healthy adult men aged between 18 and 60 years. Participants were categorized based on their habitual fiber intake, either low or high.
The findings revealed that Nutriose has a significant effect on modulating gut microbiota, particularly notable in those with a high fiber intake.
“These results underscore the potential of prebiotic soluble fiber supplementation to influence gut microbiota and serve as a preventive measure for promoting health,” the authors stated in the journal Frontiers in Nutrition.
Fibermaxxing Trend Highlights Growing Awareness of Fiber Deficiency
Dietary fibers are often under-consumed in high-income countries, leading to various health issues including metabolic, cardiovascular, gastrointestinal, and mental health problems, primarily due to their influence on gut microbiota.
Despite emerging trends and social media movements to encourage increased fiber consumption, many individuals still do not meet their fiber requirements. Soluble fiber supplements, such as resistant dextrins (RDs) like Nutriose, may help bridge this fiber gap.
Previous studies indicate that RD supplementation can enhance beneficial bacteria, such as Lactobacilli and Bacteroides, improve enzyme activity related to carbohydrate metabolism, lower fecal pH, and reduce harmful bacteria such as Clostridium perfringens. Furthermore, RD has been linked to better blood glucose management, increased feelings of fullness, improved digestion, and consistent energy levels.
“Multiple studies have affirmed the health advantages of RD related to shifts in gut microbiota that support blood glucose control, satisfaction after meals, digestive health, and sustained energy release,” the researchers pointed out. “Together, these findings confirm that RD meets the ISAPP criteria for defining a prebiotic, serving as a substrate selectively utilized by host microorganisms that confers health benefits, making it eligible for various health-related claims.”
The goal was to ascertain whether the influence of RD on gut microbiota is contingent upon an individual’s baseline dietary fiber intake.
High-Fiber Diet Enhances Response to Nutriose Supplement
Participants were categorized into low-fiber (≤15 g/day) or high-fiber (≥25 g/day) groups based on food diaries. They were then randomly assigned to receive either 15 g/day of Nutriose or a placebo for a duration of four weeks. Throughout the study, participants maintained their usual diet and lifestyle, documented their bowel habits, and provided stool samples before, during, and after the intervention, followed by a two-week washout period.
The research team analyzed stool samples to assess alterations in microbiota composition and function, examining factors such as short-chain fatty acids, pH levels, immune markers, and microbial diversity. They primarily focused on the abundance of the genus Parabacteroides, while also investigating other bacterial groups and metabolic markers.
Following the four-week supplementation period, Nutriose was found to increase the abundance of Parabacteroides, rising from approximately 1.4% at baseline to 5.5% by the end of treatment. In contrast, no changes were observed in the placebo group, and levels returned to baseline after the washout. This effect was evident in both high- and low-fiber groups, albeit slightly more pronounced in those with higher fiber intake.
Nutriose also led to an increase in specific species of Parabacteroides, particularly P. distasonis, and resulted in shifts among different bacterial groups, showing both increases and decreases within the Bacillota phylum. However, most of these microbial changes were temporary and disappeared after supplementation concluded.
Additionally, Nutriose impacted gut microbial function by enhancing genes associated with carbohydrate breakdown, especially among high-fiber participants.
“The supplementation with RD is not solely about increasing fiber intake; it offers a specific type of fiber that modifies the microbiota in terms of composition and function,” asserted the researchers.
They also indicated that the initial fiber intake levels are significant, as both high- and low-fiber groups responded positively to RD, but those already consuming higher fiber exhibited more robust and frequent microbiota changes.
“This study provides evidence that RD supplementation enhances the Parabacteroides genus within the gut microbiota, regardless of dietary fiber intake levels, with a stronger response observed in high-fiber consumers,” the researchers concluded.
However, they noted that this study involved only healthy male participants, relied on self-reported fiber intake, did not distinguish between different fiber types, and utilized maltodextrin as a placebo, which could have minor effects on microbiota. These limitations suggest directions for future research.
Source: Frontiers in Nutrition. doi: 10.3389/fnut.2026.1810842. “Resistant dextrin promotes beneficial fecal bacteria in high and low fiber diet populations: a randomized, double-blinded, controlled pilot study.” Authors: Perreau, C. et al.
