"In this thesis, Moisture MApping by Terahertz (MMAT) is proposed as a technique for the evaluation of the diabetic foot deterioration as an early diagnostic test. The image acquisition and data processing of the MMAT technique is presented together with a first clinical trial and the diagnostic potential analysis for this technique. Furthermore, a comparative analysis of three Effective Medium Theory models, namely Maxwell-Garnett, Bruggeman and Landau-Lifshitz-Looyenga, for the determination of water content in biological tissues from terahertz spectroscopic measurements is also provided in this work."