INS and Insulin resistance: Two surrogate indexes of IR, namely the homeostatic model assessment for insulin resistance (HOMA-IR) [42,43] and triglyceride-to-high density lipoprotein cholesterol ratio (TG/HDLc)—a non-insulin- and non-glucose-derived measure of β-cell function—have been correlated to the IR level as measured by the hyperinsulinemic-euglycemic clamp—considered the gold standard method—in obese children and adolescents [44,45].