On the basis of the currently available data, an increase in the uptake of indigestible roughage can be recommended as a means of reducing the risk of developing type 2 diabetes and cardiovascular diseases. In concert with other factors of a healthy lifestyle--including physical exercise, abstention from nicotine, the consumption of only moderate amounts of alcohol, reducing the intake of saturated fats, and--the main factor--ensuring that overweight does not develop, this dietary modification would appear to be an effective measure for avoiding most cases of type 2 diabetes.