In multivariate analysis, high ALT and/or high GGT levels were significantly associated with the prevalence of DM, even in non-obese groups [non-obese, low ALT, and high GGT levels (OR 1.27; 95% CI, 1.11–1.45); non-obese, high ALT, and low GGT levels (OR 2.06; 95% CI, 1.80–2.36); and non-obese, high ALT and GGT levels (OR 2.19; 95% CI, 1.89–2.52)]. Here, GPT is linked to diabetes mellitus.