(P13-26-26) Impact of Supplemental Inulin on Gut, Immune, and Vascular Outcomes in Individuals With Obesity: A Pilot Study

Objectives: Preclinical evidence suggests intestinal permeability (i.e., increased translocation of microbial antigens into circulation) drives systemic inflammation and ultimately vascular dysfunction. Though similar human data are lacking, independent studies have linked obesity with intestinal permeability, inflammation, and vascular dysfunction. Here, we conducted a time-course intervention targeting gut health (inulin supplement) in people with obesity. We hypothesized that inulin would improve intestinal permeability and inflammatory markers early in the intervention, followed by positive vascular changes.

Methods: Participants (18-55 years) with obesity (BMI ≥ 30.0 kg/m²) and no other chronic diseases were enrolled in this single-arm study (current N=13/20). The intervention consisted of a 1-wk run-in (50% dose), followed by 8 wks of inulin supplementation (12g/d; Fibruline^TM chicory root fiber). Throughout the study, participants completed three in-laboratory visits (0, 4, and 8 wks), where blood samples were collected and vascular measurements were performed including flow-mediated dilation (FMD), augmentation index normalized to heart rate (AIx@HR75), and carotid-femoral pulse wave velocity (PWV). Circulating biomarkers of intestinal permeability and inflammation will be assessed at a later date. Self-reported digestive symptoms were also explored (Digestive Pain Visual Scale). Data were analyzed with one-way, repeated measures ANOVAs.

Results: Participants (35 ± 11 years; 38% male) had a BMI of 39.9 ± 5.5 kg/m² and body fat percent of 47.7 ± 11.2%. Currently, 4- and 8-wk FMD (p = 0.463; ηp² = 0.062), AIx@HR75 (p = 0.809; ηp² = 0.018), and PWV (p = 0.627; ηp² = 0.025) were unaltered by inulin compared to week 0. Though nonsignificant, digestive pain intensity (p = 0.203; ηp² = 0.135) and unpleasantness (p = 0.113; ηp² = 0.180) were associated with ~large effect sizes consistent with decreased digestive pain.

Conclusions: The impact of inulin on vascular health in individuals with obesity remains unclear, though early evidence suggests inulin can improve digestive symptoms. Completion of this study will provide insights on the effects of inulin on indicators of gut, immune, and vascular health in obesity.

Funding Sources: Internal Funding at Ball State University