This communication hypothesises a rule of two thirds which seems to operate in Indian diabetes epidemiology. Two thirds of all persons with dysglycemia are prediabetic; two thirds of all persons with diabetes are diagnosed to have the condtion; and two thirds are diagnosed before the age of 50 years. Two thirds of people with diabetes have concomitant hypetension or dyslipidemia; two thirds do not get their HbA1c assessed; and two thirds of those who do, do not achiev target values. Yet, two thirds of people with diabetes report satisfactory psychosocial health and quality of life, and adherence to dietary therapy and medication. Only one thirds adhere to exercise and self monitoring advice, however. Two thirds of persons on oral glucose lowering drugs receive metformin; two thirds of those on insulin receive premixed insulin or twice daily isnuslin, and a similar proportion uses pens for delivery. Thus, the rule of two thirds, rather than of halves, operates in modern Indian diabetes practice.
Keywords: Epidemiology; India; prediabetes; rule of halves; type 2 diabetes.