Japanese L-carnitine Quantum & theoretical chemistry aortic stiffness atrial fibrillation biomarkers body mass index cardiovascular disease mortality cardiovascular diseases cardiovascular health cardiovascular risk estimates cardiovascular risk factors cholesterol uptake capacity (CUC) choline elaidic acid fish fructose glucose heart failure hemorrhagic stroke high-density lipoprotein (HDL) hypertension inflammatory mediators ischemic stroke lecithin-cholesterol acyltransferase (LCAT) left ventricular diastolic dysfunction meta-analysis n-3 polyunsaturated fatty acid n-3 polyunsaturated fatty acids n/a