Higher β-Glucan and Inulin Intake Linked to Lower Crohn’s Disease Risk in At-Risk Relatives

Higher dietary intake of the fermentable fiber subtypes β-glucan and inulin was associated with a reduced risk of Crohn’s disease (CD) among first-degree relatives of patients with CD, according to findings from a prospective cohort study that also identified microbiome-dependent differences in the observed associations.

Investigators analyzed data from 3314 asymptomatic first-degree relatives enrolled in the Genetic, Environmental, Microbial Project. Participants completed baseline food frequency questionnaires, provided biologic samples, and were followed for a median of 8.5 years. During follow-up, 94 participants developed CD.

Higher estimated intake of β-glucan was associated with a 30% lower risk of incident CD (hazard ratio [HR], 0.70; 95% CI, 0.54-0.92), while higher inulin intake was associated with a 32% lower risk (HR, 0.68; 95% CI, 0.49-0.96).

The protective associations varied according to baseline microbial composition. The investigators reported that “associations were strongest in those with higher baseline relative abundance of Erysipelotrichaceae UCG-003, but weaker with higher Colidextribacter.”

Beyond disease incidence, higher β-glucan and inulin intake was associated with biologic measures consistent with improved intestinal health. Participants with higher intake had lower lactulose-mannitol ratios, suggesting better gut barrier function, lower abundance of the pathobionts Ruminococcus torques and Lachnoclostridium, and lower concentrations of inflammatory and barrier-related proteins, including C-reactive protein, triggering receptor expressed on myeloid cells-1, oncostatin M, and matrix metalloproteinase 9.

The authors concluded that “higher estimated β-glucan and inulin intake was associated with preserved gut barrier function, lower systemic inflammatory markers, and lower CD risk, which was modified by the microbial context.”

Reference

Xue M, McShane C, Kim J, et al. β-Glucan and inulin estimated intake are associated with reduced risk of Crohn's disease, improved gut barrier and systemic inflammation markers, and multi-omic signatures in a high-risk cohort. Gastroenterology. Published online May 28, 2026. doi:10.1053/j.gastro.2026.05.006.