(P26-39-26) Serum Metabolomic Markers of Dairy Products

Objectives: We aimed to discover novel objective biomarkers of dietary intake of milk, yogurt, and cheese.

Methods: Cross-sectional analyses were conducted in 3,913 participants with available dietary and metabolomics data in the Atherosclerosis Risk in Communities (ARIC) study comprised of black and white men and women from four U.S. communities. Dietary intake was assessed at visit 1 (1987-1989) using a semi-quantitative Willett food frequency questionnaire administered by trained interviewers. Participants provided fasting blood samples at visit 1 which were stored at -80°F until untargeted metabolomic profiling using gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry (Metabolon) in two independent subgroups in 2010 and 2014. Multivariable linear regression models were used in each subgroup. Fixed effects meta-analysis was used to combine estimates across subgroups.

Results: In the overall sample, mean age was 54 years, 60% were women, and 61% were black. The mean intake of milk, cheese, and yogurt was 0.7, 0.4, and 0.1 servings/day, respectively. A total of 59 serum metabolites were significantly associated with milk consumption after adjusting for covariates (age, sex, race, education, physical activity, alcohol, smoking, body mass index, and estimated glomerular filtration rate) and accounting for multiple comparisons (false discovery rate < 0.05). The most common pathway among the significant milk-related metabolites was lipids (n=21), followed by amino acids (n=11), xenobiotics which include food-derived compounds (n=8), carbohydrates (n=7), cofactors and vitamins (n=5), peptides (n=5), and nucleotides (n=2). Twelve metabolites were significantly associated with yogurt and four were associated with cheese. Most metabolites were unique to each type of dairy product except for 2-aminoheptanoate which was associated with milk and cheese and glycerate, stachydrine, pyridoxate, and threonate which were associated with milk and yogurt.

Conclusions: The candidate biomarkers of milk, yogurt, and cheese represented a variety of types of compounds related to their nutritional composition. Significant dairy-related metabolites were largely unique to each dairy product, allowing for specificity in objectively characterizing dairy consumption.

Funding Sources: NIH