Coarse Grain Preference, Gut Microbiota Features, in Relation to Hypertriglyceridemia in Constipation Patients: A Cross-Sectional Study.

Coarse grain (CG) benefits blood lipids involving gut microbiota regulations. Little is known about the relation between CG preference and blood lipids in constipation patients, and related gut microbiota features. Gut microbial genera and dietary information of 249 functional constipation participants are characterized by 16S rRNA sequencing and a food frequency questionnaire. CG preference was defined as a higher CG intake frequency than refined grain (RG) intake frequency. Compared with RG, CG preference was associated with a lower serum triglyceride (TG) (p = 0.015) and a lower risk of hypertriglyceridemia (HTG). The reallocations from RG to CG at frequencies of 3, 5, and 10 times per week were associated with reductions in the risk of HTG by 48%, 67%, and 89%, respectively. A machine learning based model using gut microbiota features well identified the likelihood of HTG, with the area under the curve achieving 0.79 (95% CI, 0.65-0.91). Furthermore, the microbiome risk score profiling HTG was negatively correlated with CG preference (r = -0.150, p = 0.021). Preferring coarse grain as a staple food was associated with lower HTG risk and differential gut microbiota features in constipation patients.