Comment on: Knop et al. (2007) Reduced Incretin Effect in Type 2 Diabetes: Cause or Consequence of the Diabetic State? Diabetes 56:1951–1959

In the excellent article by Knop et al. (1), the authors use an interesting design to show that the decreased incretin effect observed in patients with type 2 diabetes is a consequence of the diabetic state rather than a causal factor. However, analyses concerning glucagon-like peptide-1 (GLP-1) concentrations seem a bit disturbing. Looking at Fig. 3 in their article, it is obvious that a 50-g glucose ingestion induces a peak of intact GLP-1 concentrations in patients …