Tehran University of Medical Sciences Acta Biochimica Iranica 0001-5261 1 2 2023 11 11 83 89 Somayeh Chahkandi Metabolic Diseases Research Center, Zanjan University of Medical Sciences, Zanjan, Iran. Reza Dabiri Department of Internal Medicine, Kowsar Hospital, Student Research Committee, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran Majid Mirmohammadkhani Social Factors Affecting Health Research Center, Department of Social Medicine, Semnan University of Medical Sciences, Semnan, Iran. Nasrin Amiri-Dashatan Metabolic Diseases Research Center, Zanjan University of Medical Sciences, Zanjan, Iran. Mehdi Koushki Department of Clinical Biochemistry, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran 2023 11 11 Objectives: The aim of this study was to evaluate the effect of silymarin on liver enzyme levels and serum lipid profiles in patients with Non-Alcoholic Fatty Liver Disease (NAFLD), the most common chronic liver disease worldwide. Methods: This randomized double-blinded clinical trial included 80 NAFLD patients referred to the gastrointestinal clinic of Kowsar Hospital in Semnan. Forty of these patients were supplemented with 150 mg of silymarin twice a day for two months, while the other 40 received a placebo. Both groups were advised to follow a hypertriglyceridemia correction and lifestyle modification. Evaluation of serum lipid profiles and liver enzymes in both groups were performed at the baseline and after two months. Results: The results showed that silymarin use significantly reduced ALT (U/L) (58.72±32.16 vs 42.2 ± 20.2, p = 0.003) and AST (U/L) (36.62± 13.46 vs 30.3 ± 9.7, p = 0.036) levels compared with the placebo group. Additionally, a statistically significant reducing effect of silymarin on triglycerides (mg/dL) (189.5 ± 65.5 vs 164.6 ± 91.3, p = 0.026), total cholesterol (mg/dL) (192.8 ± 40.3 vs 174.07± 34.5, p = 0.027), and LDL-cholesterol (mg/dL) (114.6±33.9 vs 95.6± 26.5, p = 0.012) levels was found, with no significant statistical difference for HDL-C (mg/dL) (41.5 ± 6.8 vs 43.5± 9.2, p = 0.44). Conclusion: Silymarin, at a dose of 150 mg twice daily, significantly reduced liver enzymes and some lipid markers in patients with NAFLD, suggesting that this compound could be a novel therapy for NAFLD. https://abi.tums.ac.ir/index.php/abi/article/view/32 https://abi.tums.ac.ir/index.php/abi/article/download/32/17