Poster Theater Flash Session
Objectives : Collecting dietary intake data is associated with challenges due to the subjective nature of self–administered instruments. In contrast, biomarkers of food intake can objectively estimate the consumption of specific dietary items or help assess compliance in intervention studies without self-reporting bias. Our aim was to evaluate urine and plasma biomarkers to assess compliance with a Mediterranean diet (MD) intervention and the validity of a modified Mediterranean Diet Scale (mMDS) among firefighters
Feeding America’s Bravest is a MD cluster-randomized control trial among the 44 fire stations of the Indianapolis Fire Department. In this pilot study we randomly selected a subgroup of participants (n=48) that had been assigned to a MD intervention (n=24) or a control group (n=24) for a 12-month period (the baseline for this study). The participants in the control group cross-over to the intervention for another 6 months and participants in the intervention stayed in a self-sustained-phased. Food frequency questionnaire (FFQ), mMDS and lifestyle information, urine (tyrosol and hydroxityrosol) and 40 plasma fatty acid (including oleic acid, ω-3, ω-6) and inflammatory biomarkers were analyzed at both time points. Linear, t-tests, and spearman regression coefficients were calculated using SAS software.
Results : mMDS derived from the FFQ was highly correlated with the mMDS (ρ = 0.74). After 6 months intervention plasma saturated fatty acid decreased in both groups (control- at baseline: mean difference -1.3±1.7; p=0.002; and Intervention at baseline: -1.12±1.90; p=0.014) and oleic acid improved in the intervention (p=0.013).There was a significant positive linear association between spoons of olive oil consumed and the urine hydroxytyrosol and tyrosol after 6 months (R2=0.27; p=0.039) after adjusting by group. Plasma ω-3 was inversely associated with red and processed meats (p=0.045) and positively associated with mMDS (p=0.021)
Conclusions : In this MD randomized control trial, key plasma and urine biomarkers such as ω-3 or tyrosol and hydroxytyrosol were associated with key MD diet components (e.g. olive oil) and the overall mMDS. This helps support the validity of the mMDS questionnaire as well as compliance of the intervention. Future analysis will elucidate if that translates to health benefits.
Funding Sources : EMW-2014-FP-00612, US Department of Homeland Security
Research Innovation Grant College of Health Sciences and Professions, Ohio University
Ohio University Research Council