After the proposal of diagnostic criteria for diabetes mellitus by the National Diabetes Data Group (1979) and by WHO (1980), a committee was set up by the Japan Diabetes Society (JDS) to reconsider the old criteria by the JDS which had been proposed in 1970. Items covered by the report of the committee in 1982 included the concept of diabetes mellitus, describing it's features, and stating that it's diagnosis is a procedure of recognizing the disease 'diabetes' characterized by these features. Cutoff blood glucose values for fasting samples, after a 75 g oral glucose tolerance test, were proposed to define normal and diabetic types. The cutoff values for the diabetic type are identical to those of the WHO defining diabetes, whereas the values for the normal type (fasting < 110 mg/dl and 1-h < 160 and 2-h < 120 mg/dl for venous plasma) are much lower than those for the lower limit of IGT by the WHO. Subjects whose glucose tolerance is neither diabetic nor normal are classified as borderline type, which includes not only IGT but cases with milder glucose intolerance. The cutoff points for the normal type were selected based on the long-term follow-up data for mild glucose intolerance in Japan. The Committee further stated that the clinical diagnosis of diabetes should be made not only on the basis of the glucose tolerance data, but also after clinical consideration of the possibility of any other diseases which might impair glucose tolerance.