Adherence to the Mediterranean diet is associated with the severity of non-alcoholic fatty liver disease

Background & aims: Nutrition has been proposed as a potential environmental factor affecting the risk of non-alcoholic fatty liver disease (NAFLD). In the present study, the impact of adherence to the Mediterranean diet (MD) on the presence and severity of NAFLD was explored. Methods: Seventy-three consecutive adult patients with recent NAFLD diagnosis were included. Adherence to the MD was estimated with MedDietScore. Demographic and anthropometric data, body composition analysis and several biochemical and inflammatory markers were estimated. Liver stiffness measurements by transient elastography were available in 58 patients and liver biopsies in 34 patients. Fifty-eight patients were matched with 58 healthy controls in terms of age, sex and body mass index. Results: MedDietScore was negatively correlated to patients' serum alanine aminotransferase (p = 0.03) and insulin levels (p = 0.001), insulin resistance index (p = 0.005) and severity of steatosis (p = 0.006) and positively to serum adiponectin levels (p = 0.04). Patients with non-alcoholic steatohepatitis (NASH) exhibited lower adherence to MD (29.3 +/- 3.2 vs. 34.1 +/- 4.4, p = 0.004) compared to those with simple fatty liver. Logistic regression analysis revealed that one unit increase in the MedDietScore was associated with 36% lower likelihood of having NASH (odds ratio: 0.64, 95% confidence interval: 0.45-0.92), after adjusting for sex and abdominal fat level. No difference in the MedDietScore was observed between patients and controls. Conclusions: Higher adherence to the Mediterranean diet is not associated with lower likelihood of having NAFLD, but it is associated with less degree of insulin resistance and less severe liver disease among patients with NAFLD. (C) 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.