The effect of a Mediterranean diet with adequate dairy foods on cardio-metabolic and cognitive health outcomes

This is a randomised cross-over dietary intervention trial with two 8-week dietary phases (Mediterranean diet and low fat diet) separated by an 8 week washout period. Total duration of the trial is 24 weeks. At baseline, volunteers will meet with the dietitian, for approximately 30 minutes, and receive instructions regarding their dietary prescription for the next 8 weeks. Volunteers will be prescribed their allocated diet, receive a recipe book (The Mediterranean Diet, Catherine Itsiopoulos, Pan Macmillan Australia Pty Ltd) and a sample menu (if MedDairy group) to help guide food choices. Volunteers will be given advice on eating out strategies to assist with compliance to their allocated diet. They will be issued a diet checklist to ensure they are complying with the diet. During the MedDairy phase, volunteers will receive foods characteristic of the MedDiet (olive oil, canned fish, nuts etc.) to assist with compliance. All volunteers will be asked to maintain their usual exercise pattern. Volunteers will be asked to return fortnightly to see the dietitian (for 15-30 minutes), have their weight measured return checklists, collect study foods and discuss any problems that may have arisen during the intervention. During the washout periods between diet phases, volunteers will be asked to return to following their habitual diet. Mediterranean DAIRY diet (MedDairy) The MedDiet is characterised by a variety of foods including wholegrain cereals, nuts, legumes, olive oil, red wine, small amounts of red meat, low intakes of dairy (mainly yoghurt and cheese), fish, red wine, fruits and vegetables. For this study the MedDairy diet will be based on the PREDIMED-EVOO diet however volunteers will consume 3-4 serves of low-fat and regular dairy products including cheese, milk and yoghurt. To ensure we meet the Australian recommendations for dairy foods, we are recommending 3-4 serves of dairy foods per day. Guidelines for following the MedDairy diet are adapted from Estruch R et al 2013 NEJM, include: Abundant use of extra virgin olive oil for cooking and dressing vegetables and salad 3-4 daily servings of reduced fat milk (1 cup), yoghurt (200g) and tzatziki dip (200g), regular fat cheese (40g hard/semi-soft cheese, 120 g soft cheese) 2-3 or more daily servings of fresh fruits including 100% natural juices 3 or more weekly servings of legumes (75g per serve) 3 or more weekly servings of fish and seafood (at least one serving of oily fish) (100g per serve) 3 or more weekly serving of nuts (7.5g hazelnuts, 15g walnuts, 7.5g almonds) or seeds (30g per serve) Ad-libitum consumption of wholegrain cereal products (bread, pasta, rice, cereal), nuts, fish, eggs and raw and cooked vegetables. Select white meats (poultry without skin) instead of red meats or processed meats (burgers, sausages, deli meats) Limit consumption of cured ham, red meat (remove all visible fat) to 1 or less serve/week Remove chicken skin Cook regularly (at least twice a week) with tomato, garlic and onion Dress vegetables, pasta, rice and other dishes with tomato, garlic and onion Eliminate or limit the consumption of cream, butter, margarine and discretionary foods Low-fat diet (LFD) The LFD will be based on the PREDIMED control diet (Estruch R et al 2013 NEJM) following American Heart Association in combination with local recommendations for the Heart Foundation of Australia. Volunteers will maintain the basis of their habitual diet however will be asked to modify their intake to choose low fat foods. Specifically : cook with little fat, remove / skim fats from foods, choose and purchase low fat foods