Effects of Mediterranean Diet in Patients with Nonalcoholic Fatty Liver Disease: A Systematic Review, Meta-Analysis, and Meta-Regression Analysis of Randomized Controlled Trials

Abstract

We conducted a meta-analysis to investigate the effects of the Mediterranean Diet (Med-Diet) on hepatic steatosis and insulin resistance in patients with nonalcoholic fatty liver disease (NAFLD). Six randomized controlled trials were selected for the meta-analysis (sample size: 250 participants). In the meta-analysis, there was no significant difference in body mass index and waist circumference between the Med-Diet and control groups. Med-Diet significantly reduced fatty liver index (FLI) compared with the control diet (standard mean difference [SMD]: –1.06; 95% CI: –1.95 to –0.17; p = 0.02). Med-Diet significantly reduced homeostasis model assessment of insulin resistance (HOMA-IR) compared with the control diet (SMD: –0.34; 95% CI: –0.65 to –0.03; p = 0.03). Similarly, a meta-regression analysis using age showed that Med-Diet significantly reduced FLI and HOMA-IR (95% CI: –0.956 to –0.237, p = 0.001 and 95% CI: –0.713 to –0.003, p = 0.048, respectively). This meta-analysis demonstrated that Med-Diet improved hepatic steatosis and insulin resistance in patients with NAFLD. Thus, Med-Diet is a beneficial pharmaconutritional therapy in patients with NAFLD.

Keywords

Mediterranean diet - nonalcoholic fatty liver disease - metabolism - lipid metabolism - insulin resistance - liver stiffness

Authors' Contributions

T. K. and M. C. participated in study conception and design. T. K., A. K., and S. Y. participated in data search and data extraction. T. K. and A. K. participated in the quality assessment of the studies. T. K. and A. K. participated in the analysis. D. N., T. T., M. Z., and T. T. participated in the acquisition of data and interpretation of data. T. K., S. Y., D. N., M. Z., and T. T. participated in the drafting of the manuscript. M. C. and T. T. participated in critical revision.

Disclosure

T. K. received lecture fees from MSD K.K., Mitsubishi Tanabe Pharma Corporation, and Otsuka Pharmaceutical Co., Ltd. Dr. Kawaguchi reports grants from the Research Program on Hepatitis from Japan Agency for Medical Research and Development (AMED) under Grant Number JP20fk0210040 during the conduct of the study, personal fees from MSD K.K., personal fees from Mitsubishi Tanabe Pharma Corporation, personal fees from Otsuka Pharmaceutical Co., Ltd., outside the submitted work.

Publication History

Article published online:
19 June 2021

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