Lipidomic and Fatty Acid Biomarkers in Whole Blood Can Predict the Dietary Intake of Eicosapentaenoic and Docosahexaenoic Acids in a Danish Population

Background The intake of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been associated with health benefits. Blood levels of these fatty acids by gas chromatography (GC) are associated with their dietary intake but the relationships with lipidomic measurements are not well defined. Objective To determine the lipidomic biomarkers in whole blood that predict intakes of EPA+DHA and examine the relationship between lipidomic and GC-based n-3 polyunsaturated (n-3 PUFA) biomarkers. Methods Lipidomic and fatty acid analyses were completed on 120 whole blood samples collected from Danish participants. Dietary intakes were completed using a web-based 7-day food diary. Stepwise multiple linear regression was used to identify the fatty acid and lipidomic variables that predict intakes of EPA+DHA and to determine lipidomic species that predict commonly used fatty acid biomarkers. Results Stepwise regression selected lipidomic variables with an R2=.52 for predicting EPA+DHA intake compared to R2=.40 for the selected fatty acid GC-based variables. More predictive models were generated when the lipidomic variables were selected for women only (R2 = .62, n=68) and men only (R2=.72, n=52). Phosphatidylethanolamine plasmalogen species containing EPA or DHA tended to be the most predictive lipidomic variables. Stepwise regression also indicated that selected lipidomic variables can predict commonly used fatty acid GC-based n-3 PUFA biomarkers as the R2 values ranged from .84 to .91. Conclusions Both fatty acid and lipidomic data can be used to predict EPA+DHA intakes and fatty acid GC-based biomarkers can be emulated by lipidomic species. Lipidomic-based biomarkers appear to be influenced by sex differences probably in n-3 PUFA and lipoprotein metabolism. These results improve our ability to understand the relationship between novel lipidomic data and gas chromatography fatty acid data and will increase our ability to apply lipidomic methods to fatty acid and lipid nutritional research.