There is overwhelming evidence from studies in the USA, Finland, China, India and Japan that lifestyle changes (achieving a healthy body weight and moderate physical activity) can help prevent the development of type 2 diabetes in those at high risk. The new IDF strategy advocates that this should be the initial intervention for all people at risk of developing type 2 diabetes, as well as the focus of population health approaches.
There is growing evidence that earlier detection of individuals with IGT (impaired glucose tolerance) and others at high risk of developing diabetes, followed by interventions to delay or prevent type 2 diabetes and improve glucose control, can result in clinically important reductions in the incidence of diabetes and its complications and co-morbidities.
Malmö study 
Da Qing study