While having NAFLD or having an increased BMI alone was not associated with an increased ALT, the interaction between having NAFLD and BMI was, with patients with NAFLD who had an increased BMI being more likely to have an increased ALT with an adjusted OR of 2.37 (95%CI 1.01–5.54, p = 0.046). This evidence concerns the gene GPT and metabolic dysfunction-associated steatotic liver disease.