The literature on the impact of dietary carbohydrates in the regulation of blood glucose levels and other metabolic abnormalities in diabetic patients over the last 3 years is reviewed. We try to differentiate the metabolic effects due to the amount of carbohydrates from those due to their different types. The review comprises a part dealing with the effects of diets having low or high carbohydrate content on body weight reduction, and a part in which the amount and the quality of carbohydrates are discussed in relation to isoenergetic diets. Overall, the data accumulated in the period considered seem to confirm that the decrease in energy intake is more important than the qualitative composition of the diet to reduce body weight, but that both the amount and the quality of carbohydrates are important in modulating blood glucose levels and other cardiovascular risk factors in both the fasting and the postprandial phases in diabetic individuals.