(P29-008-24) Associations Between Fiber Intake and Gastrointestinal Inflammation Between FUT2 Secretors and Non-Secretors in Healthy Adult Cohort

Objectives: The purpose of this project was to examine associations between reported fiber intake and markers of gastrointestinal (GI) inflammation between alpha(1,2)fucosyltransferase (FUT2) secretor and non-secretor genotypes in a healthy human adult population.

Methods: Throughout a cross-sectional trial of 358 healthy adults, participants completed up to three 24-hour dietary recalls using the Automated Self-Administered Dietary Assessment Tool^® (ASA24) and a Block 2014 Food Frequency Questionnaire (FFQ) to assess recent and habitual fiber intake, respectively. Inflammation markers from stool, including calprotectin, neopterin, and myeloperoxidase were measured by ELISA along with LPS-binding protein (LBP) from plasma. Genomic DNA extracted from whole blood was used to genotype a single nucleotide polymorphism (SNP) in the human FUT2 gene (SNP ID: rs601338) using TaqMan Genotyping Assays. Those who provided stool samples and blood for DNA genotyping were included in this analysis.

Results: Non-secretors (FUT2^-/-) composed 20% (n = 71) and secretors (FUT2^+/-, FUT2^+/+) composed 80% (n = 278) of genotyped participants. Using regression analysis, we observed a negative correlation between recent fiber intake and calprotectin levels among secretors (n = 228, β = -0.061, p = 0.00002), but not non-secretors (n = 60, β = 0.007, p = 0.8). Similarly, habitual fiber intake was negatively correlated with calprotectin in secretors (β = -0.044, p = 0.00005) but not non-secretors (β = 0.015, p = 0.45). The FFQ distinguishes between insoluble and soluble fiber intake, and habitual soluble fiber intake was negatively correlated with calprotectin in secretors (β = -0.13, p = 0.0002) but not non-secretors (β = 0.072, p = 0.34). Soluble fiber intake was also negatively correlated with myeloperoxidase levels in secretors (β = -0.12, p = 0.004) but not non-secretors ((β = 0.13, p = 0.2). There were no statistically significant associations between fiber intake and neopterin or LBP levels among secretors or non-secretors.

Conclusions: In a cohort of adults not diagnosed with inflammatory diseases, reduced amounts of some GI inflammation markers in stool samples were associated with higher fiber intake among FUT2 secretors, but not non-secretors.

Funding Sources: U.S. Department of Agriculture, Agricultural Research Service