T2D prevention by physical activity or diet or both proved cost-effective according to accepted thresholds , except for five inconclusive studies , three on diabetes prevention and two on obesity control .
This confirms that lifestyle interventions for the primary prevention of diabetes are cost-effective .
To summarize key findings of economic evaluations of lifestyle interventions for the primary prevention of  type 2 diabetes ( T2D ) in high-risk subjects .
The Indian Diabetes Prevention Programme shows that lifestyle modification and metformin prevent type 2 diabetes in Asian Indian subjects with impaired glucose tolerance (IDPP-1)
Aims /hypothesisLifestyle modification helps in the primary prevention of diabetes in multiethnic American , Finnish and Chinese population s. In a prospect i ve community-based study , we tested whether the progression to diabetes could be influenced by interventions in native Asian Indians with IGT who were younger , leaner and more insulin resistant than the above population s. Methods We r and omised 531 ( 421 men 110 women ) subjects with IGT ( mean age 45.9±5.7 years , BMI 25.8±3.5 kg/m2 ) into four groups . Group 1 was the control , Group 2 was given advice on lifestyle modification ( LSM ) , Group 3 was treated with metformin ( MET ) and Group 4 was given LSM plus MET . The primary outcome measure was type 2 diabetes as diagnosed using World Health Organization criteria . Results The median follow-up period was 30 months , and the 3-year cumulative incidences of diabetes were 55.0 % , 39.3 % , 40.5 % and 39.5 % in Groups 1–4 , respectively . The relative risk reduction was 28.5 % with LSM ( 95 % CI 20.5–37.3 , p=0.018 ) , 26.4 % with MET ( 95 % CI 19.1–35.1 , p=0.029 ) and 28.2 % with LSM + MET ( 95 % CI 20.3–37.0 , p=0.022 ) , as compared with the control group . The number needed to treat to prevent one incident case of diabetes was 6.4 for LSM , 6.9 for MET and 6.5 for LSM + MET . Conclusions /interpretationProgression of IGT to diabetes is high in native Asian Indians .  Both LSM and MET significantly reduced the incidence of diabetes  in Asian Indians with IGT ; there was no added benefit from combining them
T2D prevention by physical activity or diet or both proved cost-effective according to accepted thresholds , except for five inconclusive studies , three on diabetes prevention and two on obesity control .
This confirms that lifestyle interventions for the primary prevention of diabetes are cost-effective .
To summarize key findings of economic evaluations of lifestyle interventions for the primary prevention of  type 2 diabetes ( T2D ) in high-risk subjects .