INS and Impaired glucose tolerance: A number of prospective studies identified metabolic biomarkers including branched chain and aromatic amino acids, sugars and carbohydrates, and lipids (phospholipids, triglycerides) to be associated with the incidence of prediabetes (ie, impaired glucose tolerance, impaired fasting glucose, INS resistance, or impaired INS sensitivity) and type 2 diabetes (17).