In this study, using global, untargeted metabolomics and an HNF4α exon swap (α7HMZ) mouse model that happens to express low levels of the enzymes (FADS1, EPHX1, ACOX1/2, CYP2Cs) that metabolize LA (and ALA) into oxylipins, we show that lower levels of LA/ALA diols in the liver correlate with resistance to soybean oil-induced obesity, reinforcing our previous finding that elevated levels of hepatic oxylipins in WT livers correlate positively with obesity (7) (Fig. 10A). This evidence concerns the gene EPHX1 and obesity due to melanocortin 4 receptor deficiency.