Exercise or exercise and diet for preventing type 2 diabetes mellitus

In Western countries, type 2 diabetes mellitus affects up to 7% of the population. Its incidence is associated with the 'Westernised lifestyle', mainly in terms of dietary habits and physical activity. An increasing incidence of the disease is already seen in both industrialized and developing countries. There are now several Cochrane reviews of interventions to prevent and treat it, including a new review of the effects of exercise.