Linoleic Acid-Rich Oil Alters Circulating Cardiolipin Species and Fatty Acid Composition in Adults: A Randomized Controlled Trial

Scope: Higher circulating linoleic acid (LA) and muscle-derived tetralinoleoyl-cardiolipin (LA(4)CL) are each associated with decreased cardiometabolic disease risk. Mitochondrial dysfunction occurs with low LA(4)CL. Whether LA-rich oil fortification can increase LA(4)CL in humans is unknown. The aims of this study are to determine whether dietary fortification with LA-rich oil for 2 weeks increases: 1) LA in plasma, erythrocytes, and peripheral blood mononuclear cells (PBMC); and 2) LA(4)CL in PBMC in adults. Methods and results: In this randomized controlled trial, adults are instructed to consume one cookie per day delivering 10 g grapeseed (LA-cookie, N = 42) or high oleate (OA) safflower (OA-cookie, N = 42) oil. In the LA-cookie group, LA increases in plasma, erythrocyte, and PBMC by 6%, 7%, and 10% respectively. PBMC and erythrocyte OA increase by 7% and 4% in the OA-cookie group but is unchanged in the plasma. PBMC LA(4)CL increases (5%) while LA(3)OA(1) CL decreases (7%) in the LA-cookie group but are unaltered in the OA-cookie group. Conclusions: LA-rich oil fortification increases while OA-oil has no effect on LA(4)CL in adults. Because LA-rich oil fortification reduces cardiometabolic disease risk and increases LA(4)CL, determining whether mitochondrial dysfunction is repaired through dietary fortification is warranted.