- overweight/obese Chinese man (25 kg/m2<BMI<32.5 kg/m2) aged between 21 and 60 years old; prediabetes, impaired glucose tolerance (mean 2-h blood glucose ≥7.8 and ≤11.1 mmol/l after a 75-g oral glucose challenge) or impaired fasting glucose (mean fasting blood glucose ≥6.1 mmol/l and ≤7.0 mmol/l and HbA1c levels between 5.7% and 6.4%).