A randomised controlled trial of a Mediterranean Dietary Intervention for Adults with Non Alcoholic Fatty Liver Disease (MEDINA): study protocol

Background: Non-alcoholic fatty liver disease, the most prevalent liver disease in developed countries, remains difficult to manage with no proven safe and effective pharmacotherapy available. While weight reduction is the most commonly practiced treatment strategy, this is difficult to both achieve and/or maintain in the majority. Furthermore evidence-based dietary recommendations to guide the nutritional management of these patients are lacking. Using a randomised controlled trial design, this study compares the effectiveness of the Mediterranean diet to a standard low fat diet in terms of differences in insulin sensitivity, hepatic steatosis and metabolic outcomes in participants with non-alcoholic fatty liver disease. Methods: Ninety four eligible patients who have non-alcoholic fatty liver disease and who are insulin resistant, will be randomised into either a Mediterranean or low fat diet group for a 3 month intervention period. Insulin sensitivity will be measured on peripheral blood using Homeostatic Model Assessment and liver fat content quantified using Magnetic Resonance Spectroscopy. Both arms will consist of three face to face and three telephone call follow up consultations delivered by an Accredited Practicing Dietitian. The intervention arm focuses on recommendations from the traditional Mediterranean diet which have been tailored for use in the Australian population The standard arm uses the Australian Guide to Healthy Eating and the Australian National Heart Foundation dietary guidelines. Study recruitment will take place at four major metropolitan hospitals in Melbourne, Australia. Data collection will occur at all face to face reviews including baseline, 6, and 12 weeks. A follow up assessment to measure sustainability will take place at 6 and 12 months. The primary end point is improved insulin sensitivity scores at the 12 week time point. Discussion: This trial aims to demonstrate in a large cohort of participants with NALFD that a Mediterranean diet independent of weight loss can result in significant benefits in liver fat and insulin sensitivity and that these changes are sustained at 12 months. These metabolic changes would potentially lead to reductions in the risk of chronic liver disease, heart disease, type 2 diabetes and liver cancer.