Several studies have supported the usefulness of the triglycerides and glucose (TyG) index as a surrogate measure of insulin resistance; however, it has not been evaluated in insulin secretion. The aim of this study was to assess the association between the TyG index and insulin secretion in young adults with normal weight. Apparently healthy non-pregnant women and men, aged 18 to 23 years, were enrolled in a cross-sectional study. Overweight, obesity, pregnancy, smoking, alcohol consumption, diabetes, liver disease, renal disease, cardiovascular disease, and neoplasia were the exclusion criteria. Normal weight was defined by a body mass index (BMI)≥18.5