Most aspects of the nutritional therapy of diabetes mellitus apply equally to IDDM and NIDDM patients and are also appropriate for people with high risk of cardiovascular diseases. A restriction of energy, a reduction of saturated fatty acids as well as of alcoholic drinks and simple sugars are the most important measures. This modification of nutritional intake together with increased fibre consumption is not only appropriate to avoid hyperglycaemia in diabetic patients but has also its benefits in patients presenting with the metabolic syndrome (possible reduction of hyperinsulinaemia, hypertension and hyperlipoproteinaemia). Diabetic patients should have regular screening for microalbuminuria. At first signs of an early stage of nephropathy patients should be advised to restrict their protein intake. About 50% of daily energy intake should be derived from carbohydrates and fat intake should be no more than 35% of total energy (saturated fatty acids less than 10% of energy). Carbohydrate exchange units are usually not necessary in NIDDM patients. In addition diabetes specialty foods are not an essential part of the nutritional therapy. The success of the nutritional therapy in diabetic patients is substantially dependent upon qualified counselling and education of the patients by the physician (as far as possible with the assistance of a dietitian).