Type-2 diabetes, formerly known as non-insulin-dependent diabetes (NIDDM), is one of the fastest growing chronic diseases worldwide. This is primarily due to increasing prevalence of obesity, caused by a sedentary lifestyle and general food abundance. It is estimated that in year 2000 there were approximately 150 million individuals with type-2 diabetes and that this number is likely to double by 2025. A major reason for the increased diabetes prevalence is the global obesity epidemic, together addressed as “diabesity”. The global increase in the prevalence of obesity is most likely driven by a simultaneous increase in global food abundance incl. food of reduced nutritional quality, together with increased sedentariness and decreased physical activity during work and leisure time5. Recent studies have also indicated that a deviation of normal sleeping pattern (7-8 h sleep per night), particularly short sleep, increases appetite and promotes obesity and its related diseases (e.g. type-2 diabetes and cardiovascular diseases).
The main objective of PREVIEW (PREVention of diabetes through lifestyle Intervention and population studies in Europe and around the World) is to determine the extent to which a high-protein, low-Glycaemic Index (GI) diet in combination with moderate or high intensity physical activity can reduce the incidence of diabetes in pre-diabetic overweight children, adults, and elderly compared with the currently recommended diet (i.e. less protein and a higher GI). Furthermore, we want to study the interaction of lifestyle factors (diet, physical activity) with sleep and habitual stress as well as behavioural and sociological factors in the prevention of type-2 diabetes. The objectives will be achieved from two distinct lines of evidence:
1) A worldwide, multicentre, clinical randomised intervention trial (RCT) in overweight and obese pre-diabetic subjects comparing a high protein-low GI diet with the ‘officially’ recommended diet in 6 EU countries (Denmark, Finland, the Netherlands, United Kingdom, Spain, Bulgaria) and 2 overseas countries (Australia and New Zealand).
2) Longitudinal population studies using data from Europe, New Zealand and Canada with regard to the importance of protein and GI and increased physical activity for prevention of type-2 diabetes in pre-diabetic subjects.
The role of sleeping pattern and stress as well as behavioural, cultural and socioeconomic factors will be included in both types of study analyses.
