Table 1: Lifestyle Intervention Studies

Study	Features and duration	Intervention	Objective	Primary Outcome	Reduction in Incidence of diabetes
Da Qing[8,9]	577 Subjects identified to have IGT using the WHO Criteria 20 yrs. with first analysis at 6 years	The subjects were randomised into 4 groups · Control · Diet only · Exercise only · Diet and exercise Those with BMI > 25 Kg/m^2 to reduce calorie intake to lose weight to goal of BMI < 23 Kg/m^2. Those with BMI < 25 Kg/m^2, to eat more vegetables, limit sugar and alcohol.	To study whether diet and exercise interventions delayed the onset of NIDDM in an IGT population	Group-based lifestyle interventions over 6 years can prevent or delay diabetes for up to 14 years after the active intervention	Diet only group:33% (P < 0.03) exercise-only group 47% (P < 0.0005) 38% in the diet-plus-exercise group
IDDP [12]	531 subjects identified to have IGT using the WHO Criteria 3 years	The subjects were randomised into 4 groups · Control · Life Style Modifications · Metformin only · Life Style Modifications and Metformin	To study whether the progression of IGT to diabetes could be delayed in Indian population. The study population was younger leaner and more insulin resistant than the population studied in the Chinese, Finnish and the American population in whom the interventions were a success.	It is possible to prevent diabetes in native Asian Indian subjects with IGT using lifestyle modification, despite their relatively low BMI and highly insulin-resistant characteristics	Relative Risk Reduction in incidence of diabetes as compared to control: LSM: 28.5% Metformin: 26.4% LSM + Metformin: 28.2%
FDPS [10]	522 overweight subjects with IGT using the WHO criteria 3.2 years	The subjects were randomised into 2 groups Control Lifestyle Goal was of weight loss > 5%, decreased SFA intake, fibre intake of > 15 g/1000 kcal and > 30 min/day of moderate PA.	Whether type 2 diabetes can be prevented by interventions that affect the lifestyles of subjects at high risk for the disease	Primary prevention of type 2 diabetes by a non-pharmacologic intervention which can be implemented in a primary health care setting.	The overall incidence of diabetes was reduced by 58%
Swedish Malmo feasibility Study [13]	41 subjects with early type 2 diabetes and 181 subjects with IGT 6 years	The subjects were randomised into 2 groups Control Life Style Modification	To test the feasibility aspect of long-term intervention with an emphasis on life-style changes.	Improvement in glucose tolerance was correlated to weight reduction and increased fitness	Incidence of diabetes: Reference group: 29% Intervention group: 11% The incidence in the intervention group was less than half that of the other group.

Abbreviations: BMI: Body Mass Index, PA: Physical Activity, SFA: Saturated Fatty Acids