Abstract P204: Associations Between Dairy Intake and Serum Metabolites in Middle-Aged Adults in the U.S.

Introduction: There is a lack of objective biomarkers of dietary intake. Untargeted studies can unbiasedly identify dairy biomarkers and inform the creation of robust dietary assessment tools that integrate questionnaire and biospecimen data. Methods: Dairy products from interviewer-administered questionnaires were categorized as either low-fat or high-fat dairy. Total dairy was a composite of low-fat and high-fat dairy items. Linear regression models were used to assess associations between dairy intake and 360 serum metabolites in the Atherosclerosis Risk in Communities (ARIC) Study (n=3907). Significant associations were then tested for replication in the Bogalusa Heart Study (BHS) (n=819). Results: In the ARIC study, 34 dairy-metabolite associations were identified (total dairy, n = 16; low-fat dairy, n = 10; high-fat dairy, n = 8). Total dairy shared 7 metabolic associations each with low-fat dairy and high-fat dairy. Low-fat dairy was associated with pantothenate, vitamin B5, and the catabolic product of vitamin B6, pyridoxate. High-fat dairy was associated with one amino acid, 3-hydroxy-2-ethylpropionate, and eight lipid metabolites, including myristate (14:0), 10-nonadecenoate (19:1n9), and myristoleate (14:1n5). Of the metabolites available for replication in BHS (total dairy, n = 15; low-fat dairy, n = 9; high-fat dairy, n = 8), 2 total dairy metabolites were replicated and 2 low-fat dairy metabolites were replicated ( Table ). Conclusions: We identified metabolomic markers of total, low-fat, and high-fat dairy. Pantothenate, myristate (14:0), and tiglyl carnitine replicated across two large, diverse study populations, suggesting that they are markers of dairy consumption.