Non-Alcoholic Fatty Liver Disease (NAFLD): the feasibility of two different weight loss dietary approaches

This is a 6 month feasibility study. The feasibility and acceptability of two different weight loss dietary approaches will be examined. Diet A will utilise partial meal replacements (Optifast). Diet B will be provided wtih dietitian delivered dietary advice based on the 2004 recommendations for the treatment and prevention of diabetes mellitus published by the Diabetes and Nutrition Study Group of the European Association for the Study of Diabetes. The dietary treatment goal for all participants will be a 5-10% weight loss over 6 months. Diet A Group (Partial meal replacement) The rate of weight loss will be 1.0kg/week, and no more than 1.5kg/week for 4 weeks, then 0.5-1.0kg/week until weight loss goal is achieved. Participants in the Diet A group will be given partial meal replacements (Optifast) and suggested meal plans for 8 weeks by a dietitian. Partial rather than full meal replacement will be used. A gradual weight loss of <1.6 kg/week) is advisable, rather than more rapid loss, because faster weight loss is known to exacerbate liver injury. For the first four weeks 2 meals per day will be replaced with an Optifast product, followed by one meal replaced by Optifast per day for a further four weeks. From week 8 no Optifast products will be used but participants will be instructed to consume an individualised low calorie diet for the subsequent 18 weeks, until 6 months. During weeks 1-4, in addition to two Optifast meal replacements per day, the daily diet will include a light meal (500 Cal/2090 kJ), 2 pieces fruit, 1 serve low-fat dairy (250ml low fat milk, 40g/ 2 slices low fat cheese or 200g low fat yoghurt), 2 cups low starch vegetables, and 2 litres water. During weeks 5-8, in addition to one Optifast meal replacement per day, the daily diet will include a light breakfast (350 Cal/1463 kJ), one light meal (500 Cal/2090 kJ), 2 pieces of fruit, 1 serve low-fat dairy (250ml low fat milk, 40g/ 2 slices low fat cheese or 200g low fat yoghurt), 2 cups low starch vegetables, and 2 litres water. Education about healthy eating habits and low calorie meals and snacks will be included and reinforced at all appointments with the dietitian. Participants in this group will see a dietitian weekly during weeks 1-8. They will then see a nurse for ‘weigh-ins’ fortnightly for 1 month, then monthly for months 4-6. 3-day weighed diet records at baseline and 8 weeks will guide dietary advice. Dietary adherence will be monitored by the study dietitian enquiring about Optifast products consumed, and collecting empty Optifast product packages and by asking participant to complete a daily food diary. Change in body weight (kilograms) and % of liver fat as measured by Hydrogen Magnetic Resonance Spectroscopy (H-MRS) will be measured. Diet B Group (Treatment and prevention of diabetes dietary recommendations) The rate of weight loss will be 0.5-1.0kg/week until weight loss goal is achieved. Participants in the Diet B group will be provided with dietary advice based on evidence-based recommendations for the treatment and prevention of diabetes mellitus published by the Diabetes and Nutrition Study Group of the European Association for the Study of Diabetes (2004). The aim will be to achieve a gradual, but sustainable weight loss through dietary changes. Appropriate food quantities, vegetables, fruit, legumes, wholegrain cereals, fish (preferably oily), nuts, low fat dairy products and appropriate fats and oils will be emphasised. Dietary advice will be tailored to the individual taking into account culture, family, employment, budget and co-morbidities. We have previously successfully used this dietary approach in the Lifestyle Over and Above Drugs in Diabetes (LOADD) study which included patients with type 2 diabetes who had poor glucose control despite taking recommended hypoglycaemic medication. Participants in this group will see a dietitian weekly during weeks 1-8, then fortnightly for 1 month, monthly for months 4-6. They will also be weighed at each of these visits. 3-day weighed diet records at baseline and 8 weeks will guide dietary advice. Dietary adherence will be assessed by reviewing paricipant dietary goals and undertaking a diet recall at each visit. Change in body weight (kilograms) and % of liver fat as measured by Hydrogen Magnetic Resonance Spectroscopy (H-MRS) will be measured. All participants in both diet groups will be given one-off Ministiry of Health standard pamphlet, ‘Be active every day: Physical activity for adults’ exercise advice, with the aim of doing at least 30 minutes of moderate intensity physical activity most, if not, all days of the week.