Abstract
Valid measures of dietary intake are essential for health and nutrition research, but typical forms- or interview-based measurements are susceptible to random and systematic errors. Although many biomarkers of food intake (BFIs) have been validated, we aimed to explore how food-BFI relationships are affected by genetic and lifestyle factors among Caribbean Hispanic adults. Dietary, clinical, anthropometric, blood metabolomics, and genotype data from 782 Puerto Rican adults were available. Thirty-one BFI-food intake relationships were assessed using linear regression, including covariates based on significant covariate-BFI associations (i.e., age, body weight, physical activity, and sex). We observed 12 known BFI-food pairs that reached statistical significance, of which 11 remained significant after adjustment. Applying genome-wide association tests of blood metabolites to BFI-food pairs, genetic variants rs7078243 and rs62501664 were identified as modifying relationships with 3-methylxanthine-coffee and 3-methylhistidine-poultry, respectively. Eleven validated biomarker-food intake pairs remained statistically significant after adjusting for covariates. Identification of genotype-BFI associations accentuates that the implementation of certain BFIs will depend on common genetic differences.