Incretin Effect in People With Impaired Fasting Glucose

Inclusion Criteria: * Healthy, sedentary, non-smokers, men and women 45-70 years old Subjects were placed into 1 of the 2 groups based on two 2-hour 75g oral glucose tolerance tests (2h OGTT), separated by one week: a control group with normal glucose tolerance (NGT; n=14; fasting glucose \<5.6 mmol/l and 2h OGTT \<7.8 mmol/l), or IFG (n=10; fasting glucose 5.6-6.9 mmol/l, and 2h OGTT \<7.8 mmol/l). Exclusion Criteria: * Subjects were excluded for: thyroid stimulating hormone \<50 or \>500 milliunits/L, fasting triglycerides \>10.3 mmol/l, creatinine \>130 μmol/l, elevated liver function tests (\>2 times normal), hematocrit \< 38%, or white blood cell count \<3.0 x 103. Use of medications for lipid and/or glucose lowering also excluded enrollees. Women may not have used hormone replacement therapy in the past 1 year. Smokers. BMI \<25 or \>40 kg/m2. Diabetes or impaired glucose tolerance.