ABSTRACT Diabetes mellitus has a prevalence of up to 25% in the age group above 75 years and is thus a major disease of the elderly. Geriatric syndromes (e.g. immobility or falls, incontinence or intellectual decline) occur more often in the diabetic elderly. Moreover there is a mutual interaction between the syndromes and the control and therapy of diabetes. This fact can be explained by the molecular mechanisms of frailty. Advanced glycation end products, inflammatorial cytokines like IL-6 or TNF-alpha are elevated in subjects with metabolic syndrome as well as in frail elderly. Insulin has anabolic effects inhibiting protein catabolism. The situation of frail elderly with diabetes sometimes can be improved by starting an insulin therapy because of its anabolic effects beyond the action of normalizing blood glucose.