Performance of the Triglyceride-Glucose (TyG) Index for Early Detection of Insulin Resistance in Young Adults: Comparison with HOMA-IR and QUICKI in Western Mexico

Background/Objectives: Insulin resistance is a major public health issue in Mexico, closely linked to obesity, prediabetes, and type 2 diabetes. The euglycemic–hyperinsulinemic clamp is the diagnostic gold standard but is impractical for routine use. The triglyceride–glucose (TyG) index has been proposed as a simple alternative validated in diverse populations. We aimed to assess the utility of TyG relative to HOMA-IR and QUICKI as an early diagnostic tool in young Mexican adults. Methods: We performed an analytical cross-sectional study in young adults. Clinical, anthropometric, and fasting biochemical variables were collected to compute TyG. We compared TyG with HOMA-IR and QUICKI and evaluated diagnostic performance using receiver operating characteristic analysis to estimate area under the curve (AUC) and identify the optimal cut-off. Results: We analyzed 115 participants; 66.9% were insulin resistant by HOMA-IR, 79.1% by QUICKI, and 42.6% by TyG. TyG showed significant associations with anthropometric and biochemical measures. Diagnostic performance was good (AUC 0.707 vs. HOMA-IR; 0.960 vs. QUICKI). The optimal cut-off was 4.38, yielding sensitivity of 70.1% and specificity of 68.4% for diagnosing insulin resistance compared with HOMA-IR. Conclusions: The TyG index appears to be a useful, accessible, and cost-effective biomarker for early detection of insulin resistance in young Mexican adults. Its implementation could facilitate earlier diagnosis and prevention of cardiometabolic complications. Longitudinal, multicenter studies are warranted to establish population-specific reference values and to confirm its predictive value for adverse outcomes.