All plasma samples were obtained after an overnight fast before the start (i.e., after stopping all glucose-lowering medication including insulin) and after the 16-week VLCD protocol, stored in aliquots at −80°C, and analyzed after thawing once in a single laboratory (Leiden, the Netherlands). To ascertain that we could make adequate correlations, all analyses were performed within the same blood samples in the same assay runs. Plasma cholesterol and TG concentrations were determined using enzymatic kits (no. 236691 and 11488872, respectively; Roche Molecular Biochemicals, Indianapolis, IN). Plasma phospholipids were determined using the phospholipids B kit (Wako Chemicals, Neuss, Germany). Plasma CETP concentration was quantified using kit CETP ELISA Daiichi (Daiichi Pure Chemicals, Tokyo, Japan). HDL fractions were obtained after precipitation of apolipoprotein (apo)B-lipoproteins from 50 μL plasma by adding 25 μL 36% polyethylene glycol 6000 (PEG6000, no.81260; Sigma Aldrich) The HDL-cholesterol and phospholipids were determined as described above. Plasma apoAI and apoB100 levels were determined with the Human ApoAI ELISA kit (no. 3710–1H; Mabtech AB, Nacka, Sweden) and Human ApoB ELISA kit (no. 3715–1H; Mabtech AB), respectively.