1. A method for managing blood glucose levels associated with a diabetes care management treatment regimen, comprising the steps of: (a) electronically storing (i) a plurality of optimal blood glucose values at a plurality of times, (ii) a plurality of insulin dose values of a patient at said times, (iii) a plurality of measured blood glucose values at said times, and (iv) a plurality of optimal insulin dose values at said times; (b) generating and storing a plurality of scaling factors customized to said patient in response to changes in any one of said insulin dose values or said measured blood glucose values occurring at any one of said times; (c) calculating with a microprocessor a future blood glucose value based on (i) a plurality of differentials, one of said differentials calculated as one of said scaling factors multiplied by differences between one of said insulin dose values and one of said optimal insulin dose values, (ii) a sum of said differentials plus (iii) a difference between one of said measured blood glucose values and a corresponding one of said optimal blood glucose values; (d) displaying said future blood glucose value; and (e) advising said patient to take insulin in response to said displaying of said future blood glucose value.