Systematic review with meta‐analysis: The effect of vitamin E supplementation in adult patients with non‐alcoholic fatty liver disease

Abstract

Background and Aim Νon‐alcoholic fatty liver disease (NAFLD) is estimated to be the most common cause of end‐stage liver disease in the next years. Vitamin E has shown beneficial effects as a possible “scavenger” of oxidative stress products, which play a major role in pathogenesis of the disease. The purpose of the present meta‐analysis is to investigate the effects of vitamin E supplementation in biochemical and histological parameters in adult patients with NAFLD. Methods Literature search was performed in major electronic databases (MEDLINE, CENTRAL, and Embase) up to June 2020 for randomized clinical trials, which examined vitamin E versus placebo treatment in adults with NAFLD. Changes in liver enzymes were considered as primary outcomes while changes in histological, biochemical, and metabolic parameters as secondary. Quality of evidence was assessed through risk of bias according to the Cochrane risk of bias tool. Results Eight studies were included in qualitative analysis and seven in quantitative analysis. Vitamin E reduced the values of liver enzymes compared with placebo (−7.37 IU/L, 95% confidence interval: −10.11 to −4.64 for alanine aminotransferase, and −5.71 IU/L, 95% confidence interval: −9.49 to −1.93 for aspartate aminotransferase). Additionally, vitamin E improved statistically significantly liver pathology in every individual histological parameter as well as low‐density lipoprotein cholesterol, fasting blood glucose, and serum leptin values. Conclusions Vitamin E can improve biochemical and histological characteristics of NAFLD patients, especially of non‐alcoholic steatohepatitis patients. The results indicate that vitamin E could be a promising choice and be considered as a treatment option in patients with NAFLD.

How does hepatic lipid accumulation lead to lipotoxicity in non-alcoholic fatty liver disease?

“…Moreover, reducing oxidative stress (e.g. by vitamin E or metformin) also alleviates lipotoxicity [96,116]. Furthermore, the use of chemical chaperones [e.g.…”

The role of biofactors in the prevention and treatment of age‐related diseases

“…Inhibition of de novo lipogenesis by αT was also observed in vitro, where it was dependent on the antioxidant function of αT, highlighting once again the interplay between oxidative stress and steatosis 148 . A meta‐analysis of eight clinical trials (including 465 NAFLD patients) showed an overall benefit of vitamin E‐supplementation on histological parameters of NAFLD that appear to be especially pronounced in patients with NASH 149 . None of the clinical trials reported any adverse events attributed to treatment 141–143 …”

Role of the Gut Microbiota in Regulating Non-alcoholic Fatty Liver Disease in Children and Adolescents

“…In addition to dietary and exercise intervention, vitamin E supplementation is well-recognized as an anti-NAFLD therapeutic nutrient in both adults and children (148)(149)(150). Meta-analysis demonstrated that vitamin E was effective in ameliorating the biochemical and histological characteristics of adult patients with NAFLD, especially NASH (150). In children with NASH, a double-blind, placebo-controlled, randomized trial found that vitamin E treatment did not reduce ALT levels but significantly improved histologic outcomes (148).…”