Dietary fibers to boost endogenous GLP-1 secretion and satiety: a scoping review

Dietary fibers can stimulate endogenous glucagon-like peptide-1 (GLP-1) secretion through microbial fermentation and gut hormone signaling, potentially enhancing satiety and supporting weight management. Given the growing interest in non-pharmacological strategies to complement or support tapering of GLP-1 receptor agonist therapy, a structured overview of the human evidence is needed.

A pre-registered scoping review was conducted using PubMed, Scopus and Cochrane Central. Randomized controlled trials in adults assessing circulating GLP-1 concentrations and satiety following supplementation with a single, well-defined dietary fiber were included. Fiber types were categorized based on structural characteristics. Outcomes were summarized qualitatively across fiber categories.

In total, 1049 papers were screened and 49 publications comprising 52 studies (total n=1,085 participants; median sample size per study=19) were included. Most studies were acute interventions (71%) and conducted in Western populations. Studies reporting increased GLP-1 showed a non-significant tendency to also report increased satiety (OR = 2.95, 95% CI: 0.87-9.98). Dextrins stood out as one of the few fiber categories showing robust effects on both GLP-1 (4 positive studies) and satiety (5 positive studies). Other fibers, such as β-glucans and mannans, showed more uniform effects on satiety or GLP-1, respectively, but did not consistently affect both outcomes simultaneously.

Although these findings identify dextrins as a promising dietary fiber candidate for future research, the evidence remains constrained by small sample sizes, short interventions, and substantial heterogeneity. Longer-term studies in free-living conditions, including periods of GLP-1 receptor agonist tapering, are needed to capture microbiota adaptation and generate robust real-world evidence.

https://osf.io/cnw4e/overview.