A continuous blood glucose monitoring system and method measures emitted microwave energy transmitted to and accepted by blood vessels in a desired target area of a patient in order to determine, in real time and in vivo, appropriate blood glucose levels. A measurement unit comprises a transmitter operatively connected to an antenna to deliver energy towards appropriate subcutaneous blood vessels. The measurement unit determines an accepted energy power value in the blood vessels associated with the desired target area. This measurement energy power value is compared with a calibration value, and the difference is used to determine a resultant blood glucose value. The determined blood glucose value may further be acclimatized using additional sensed values compensating for biological and ambient factors relevant to the patient. The final determined blood glucose value can be displayed for reading and/or transmitted and stored for recording for further reference.