Optimal dietary macronutrient distribution in China (ODMDC): a randomised controlled-feeding trial protocol.

BACKGROUND AND OBJECTIVES: Findings from observational studies in China show that increased dietary fat consumption might be a contributor to the developing obesity epidemic. However, some cohort studies suggest that carbohydrate intake, especially from white rice, is a risk factor for obesity, type 2 diabetes and coronary heart disease in China. Our study aims to determine whether the traditional lower-fat, higher-carbohydrate Chinese or the Western higher-fat, lower-carbohydrate dietary pattern is more effective for weight control and the related cardiometabolic profiles increasingly found among contemporary Chinese.

METHODS AND STUDY DESIGN: The Optimal Dietary Macronutrient Distribution in China (ODMDC) trial is a 6-month, multi-centre, three-arm controlled feeding study. Based on the macronutrient transition in the past 30 years in China, three isoenergetic diets with a spectrum of fat and carbohydrate intake, but same protein contents, have been formulated. Percentages of fat, carbohydrate, and protein energy are one of 20, 66 and 14%; 30, 56 and 14%; 40, 46 and 14%, respectively. Participants will be provided with all their food and most beverages for 6 months.

RESULTS: The study population is planned to be 300 healthy non-obese adults aged 18 to 35 years. The primary outcome is body weight and the secondary variables are waist circumference and cardiometabolic risk factors.

CONCLUSIONS: The ODMDC trial will have implications for nutrition policy in regard to weight control and related cardiometabolic disturbances among otherwise healthy non-obese Chinese.