Background: Metabolic syndrome (MetS) is a constellation of metabolic abnormalities that significantly increases the risk of type 2 diabetes mellitus and cardiovascular disease. Insulin resistance plays a central role in its pathogenesis. While fasting insulin is traditionally used as a surrogate marker of insulin resistance, Gamma-Glutamyl Transferase (GGT), an enzyme associated with oxidative stress and hepatic steatosis, has recently emerged as a potential biomarker.

Objectives: To evaluate and compare fasting insulin and serum GGT levels as biomarkers in metabolic syndrome.

Methods: A cross-sectional study was conducted among 80 subjects diagnosed with metabolic syndrome at K.V.G. Medical College & Hospital, Sullia, over one year (August 2023–August 2024). Diagnosis was made according to the criteria proposed by the International Diabetes Federation. Fasting insulin and GGT levels were measured and correlated with metabolic syndrome components using Pearson’s correlation coefficient.

Results: Fasting insulin showed strong positive correlations with waist circumference (r=0.65), triglycerides (r=0.55), and blood pressure (r=0.48), and a negative correlation with HDL cholesterol (r=–0.60). GGT demonstrated significant positive correlations with waist circumference (r=0.55), triglycerides (r=0.57), blood pressure (r=0.57), and a negative correlation with HDL cholesterol (r=–0.45). Both biomarkers correlated strongly with overall metabolic syndrome severity.