INS and Insulin resistance: Concurrently, metabolites such as 3-hydroxykynurenine (3-OH-KYN), quinolinic acid, the kynurenine-to-tryptophan ratio, and 3-hydroxyanthranilic acid (3-OH-AA) were positively correlated with measures of glucose metabolism and insulin resistance: fasting blood glucose (FBG), fasting serum insulin (FSIns), and the homeostatic model assessment of insulin resistance (HOMA-IR).