The basis of different diets for insulin dependent and maturity onset obese diabetics is discussed. The results achieved by strict calorie control in obese diabetics are compared with those in a group of patients with simple obesity and shown to be superior. The value of very low carbohydrate lager is assessed. It is concluded (a) that there is no case for severe carbohydrate restriction in diabetic diets unless there is a need for total calorie restriction and (b) 'Diet' low carbohydrate lager offers no particular advantages over ordinary lager in the diabetic diet.