In 1980, the WHO Expert Committee on Diabetes Mellitus (DM) proposed a new classification of diabetes. In it, impaired glucose tolerance (NTG) was identified as an independent clinical class. This was due to the following: diabetes, primarily non-insulin-dependent (NIDDM), as a rule, develops gradually, and several stages can be distinguished in its development [35, 55]. The first of them, according to many experts, is NTG.