The investigators hypothesise that a common A277G polymorphism of the liver fatty acid binding protein (L-FABP) gene, which leads to an amino acid exchange, may be associated with alterations of lipid-induced hepatic insulin resistance. In the present study the investigators will investigate potential differences in lipid-induced hepatic insulin resistance, and in the relation between glycogenolysis and gluconeogenesis, in healthy subjects with the A277G polymorphism vs. subjects carrying the wildtype.