Effects of Supplementation with Different Forms of Vitamin E on Liver Enzymes: A Systematic Review of Randomized Clinical Trials

Background: Obesity and non-alcoholic fatty liver disease (NAFLD) are considered as the main causes of liver-associatedmorbidity and mortality. Antioxidant administration was proposed as a remedy for liver problems such as steatohepatitis. This systematic review aimed to examine the effects of supplementation with various forms of Vitamin E on liver enzymes. Methods: To find relevant articles, in our systematic review article, we searched PubMed, Scopus, Embase, Cochrane library, and Web of Science up to 20 MAY, 2021. Randomized controlled trials (RCTs) on the effects of vitamin E supplementation, in isolation or combined with other nutrients, on liver health were included. After excluding irrelevant records, 21 studies remained. Results: According to the results of the included studies, vitamin E, especially α-Tocopherol or its co-supplementation with other antioxidants, at specific dosage could possibly have positive effects on improving liver functions and levels of Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) enzymes. Conclusion: Vitamin E,could possibly have positive effects on improving the liver function and the levels of ALT and AST enzymes.