 Subjects with IGT in the age group of 30-55 years n900 will be identified by screening with a standard OGTT. Selected subjects will be randomized to the control arm using placebo and the two study arms using Sitagliptin. At baseline all group will receive a standard advice on lifestyle modification. The dose of sitagliptin will be 100 mgd. The subjects will be reviewed at 6 monthly intervals and repeat OGTT will be done annually. 