GPT and metabolic syndrome: The concentration of ALT, AST and GGT in the MetS + subjects was significantly higher than in the control group 7.13 IU/L (CI95% 5.73–8.54; p < 0.00001; I2 = 96%), 2.68 IU/L (CI95% 1.82–3.54; p < 0.00001; I2 = 96%) and 11.20 IU/L (CI95% 7.11–15.29; p < 0.00001; I2 = 96%), respectively.