IRS1 and metabolic syndrome: We did not measure IRS‐1 tyrosine phosphorylation after the euglycemic clamp insulin infusion, but based on studies by other groups in mice (Aguirre et al. 2002; Boura‐Halfon and Zick 2009), we infer that insulin‐stimulated phosphorylation of IRS‐1 at Tyr896 is likely impaired in the metabolic syndrome subjects with fasting hyperphosphorylation of IRS‐1 at Ser636 and/or Ser337.