Hi... Diabetes occurs because of inadequate effects of insulin over the blood sugar. They occur due to inadequate supply of insulin as in type i and following insulin receptor resistance as in type ii. Weight reduction and loss of body fat reduces the insulin resistance and there by help in better blood sugar control in type ii diabetes. Diabetes though is a condition which is often not reversible, however weight reduction measures can help in normalising mild insulin resistance and there by normalise the mild form of type ii diabetes... But when the weight reduction measures fail and the body fat increases the insulin resistance will increase resulting in type ii diabetes... Hene persistant means of body weight reduction is needed in copntrol of the sugar...