Dietary vitamin B6 intake and gallstone prevalence in US adults

Although mechanistic data implicate vitamin B6 in the regulation of cholesterol metabolism and inflammatory pathways, the epidemiological nexus between dietary vitamin B6 consumption and gallstone susceptibility remains largely uncharted in population-based cohorts. Leveraging cross-sectional data from the National Health and Nutrition Examination Survey (NHANES 2017–2023; n = 9273), we utilized weighted multivariable logistic regression to elucidate the association between vitamin B6 intake and self-reported gallstone history, with models rigorously adjusted for sociodemographic, lifestyle, and clinical confounders. Restricted cubic splines (RCS) were employed to delineate dose-response trajectories, while subgroup analyses served to identify potential effect modifiers. The overall prevalence of gallstones was 10.47% (971/9273). In fully adjusted models, a significant inverse correlation emerged between vitamin B6 intake and gallstone risk (OR per mg increase: 0.90; 95% CI: 0.82–0.99; P  = .029). RCS analysis revealed a linear dose-response gradient, with statistical significance attained at intake levels exceeding 1.6615 mg/day (P for nonlinearity = 0.249). Stratified analyses indicated a modest yet robust inverse association among adults aged 20–39 years (OR: 0.75; 95% CI: 0.56–1.00), non-Hispanic Whites, individuals with a Poverty Income Ratio (PIR) > 4, those comorbid with diabetes or hypertension, and vigorous exercisers. Elevated dietary vitamin B6 intake correlates with a diminished prevalence of gallstones in the US adult population, particularly beyond a threshold of 1.66 mg/day. These findings suggest that specific metabolic and socioeconomic subgroups may derive disproportionate protective benefits, thereby offering critical insights for the formulation of targeted preventive interventions.