To test these hypotheses, The Investigators will recruit 100 overweight and obese adolescents with HbA1c ranging across the ADA classification spectrum from normal to prediabetes,(nearly 40:normoglycemi, 30: IFG, 30:1GT) measure free-living glucose by continuous glucose monitoring (CGM), and assess the relationships among CGM outcomes, HbA1c, and OGTT results (FPG and 2-h glucose). Individual with overt diabetes will be excluded. This will be a 2 visit study. Subjects will be coming to Fortis CDOC after a minimum 8-hour overnight fast. Informed written consent and validated questionnaire in a language known to them (English/Hindi) will be obtained from all participants. Clinical details will be obtained from the case records of the patients. Note of visible markers of insulin resistance (acanthosis nigricans, buffalo hump, double chin, subcutaneous fat pads, skin) Anthropometry, skinfolds \& blood pressure will be recorded. Overweight and, obesity will be defined according to predefined guidelines for Asian Indian. Abdominal obesity is defined as waist circumference of ≥ 90 centimetres (cms) in males and ≥ 80 cms in females. A blinded iPro Continuous Glucose Monitor (Medtronic MiniMed, Inc) will be inserted. After a calibration period of 1 hour, fasting laboratory result will be collected: FPG, HbA1c. HbA1c will be done by HPLC (NGSP approved, turbid inhibition immunoassay). Then subjects will consume 1.75 g/kg glucose, maximum 75 g (glucose beverage) and will have a second venepuncture 2 hours later for plasma glucose measurement. While awaiting the 2-hour venepuncture, participants will be provided instructions on CGM device care and calibration. Participants will be instructed to wear the CGM device for a minimum of 72 hours and to not change any of their current dietary or activity habits for the period of CGM wear. They will be trained to use a glucose monitor and collect capillary blood glucose values at least three times daily, prior to meals. Participants will also be asked to complete a simple log of their activity, as well as record dietary intake, and sleep and wake times. The iPro and log-sheet will be returned in person after a minimum of 72 hours of recording time. Investigators and patients will be kept blinded to CGM recordings throughout the study. Daily glycaemic variability will be assessed by the change in the mean amplitude of glucose excursions (MAGE) index, and through the standard deviation (SD) of the mean 24-hour blood glucose concentration. Day-to-day variability will be assessed through the mean of daily differences (MoDD in mg/dL). Daily glycaemic control will be assessed by the mean (M) daily CGM value, as well as by the times (in minutes/day) spent in optimal glycaemic range (70-140 mg/dL) and above predefined hyperglycaemic thresholds (140 ,180 and 200 mg/dL) together with the corresponding area under the curve (AUC) values. In addition, areas under 24-hour glycaemic traces (AUCs) will be analysed to estimate: overall hyperglycaemia (defined asAUC≥100 mg/dL over the full 24-hour period = AUCtotal);postprandial hyperglycaemia (AUC\[0-4 h\], i.e. for four-hour periods after each of the main meals and, if considered relevant by the core laboratory, after additional snacks = AUCpp); and basal hyperglycaemia, i.e. overall hyperglycaemia - postprandial hyperglycaemia (AUCb)