1. Else Kröner-Fresenius-Center for Nutritional Medicine of the Technical University Munich (T.S., C.A.-H., H.H.), D-85350 Freising, Germany
2. the German Diabetes Clinic, German Diabetes Center (C.H.), Leibniz Center at Heinrich-Heine-University Düsseldorf, D-40225 Düsseldorf, Germany