Adherence to the DASH diet is inversely associated with T2DM risk. Metabolic changes due to DASH adherence and their potential relationship with incident T2DM have not been described.
The objective is to determine metabolite clusters associated with adherence to a DASH-like diet in the Insulin Resistance Atherosclerosis Study (IRAS) cohort and explore if the clusters predicted 5-year incidence of T2DM. The current study included the 570 non-diabetic multi-ethnic participants aged 40 - 69 years. Adherence to a DASH-like diet was determined a priori through an 80-point scale for absolute intakes of the eight DASH food groups. Quantitative measurements of 87 metabolites (acylcarnitines, amino acids, bile acids, sterols, and fatty acids) were obtained at baseline. Metabolite clusters related to DASH adherence were determined through partial least squares (PLS) analysis using R. Multivariable-adjusted logistic regression (MLR) was used to explore the associations between metabolite clusters and incident T2DM. A group of acylcarnitines and fatty acids loaded strongly on the two components retained under PLS. Among strongly loading metabolites, a select group of acylcarnitines had over 50% of their individual variance explained by the PLS model. Component 2 was inversely associated with incident T2DM (Odds ratio (OR): 0.89; 95% Confidence interval (CI) 0.80-0.99, p-value = 0.043) after adjustment for demographic and metabolic covariates. Component 1 was not associated with T2DM risk (OR: 1.02; 95% CI 0.88-1.19, p-value = 0.74). Adherence to a DASH-type diet may contribute to reduced T2DM risk in part through modulations in acylcarnitine and fatty acid physiology.