Study of Metabolic Homeostasis in Chinese

The recruited 120 subjects (60 men and 60 women aged 20-70 years) will be recruited according to the followings: 1) individuals aged 20-29 years with normal weight (18.5 kg/m2 ≤ BMI < 24 kg/m2); 2) individuals aged 30-49 years with normal weight; 3) individuals aged 30-49 years with overweight/obesity (BMI ≥ 24 kg/m2); 4) individuals aged 50-70 years with normal weight; 5) individuals aged 50-70 years with overweight/obesity; and 6) individuals aged 30-70 years with MetS. A standard questionnaire will be use to collect Information like lifestyle factors, nighttime sleep duration; anthropometric measurements will be performed. Blood samples will be collected via a catheter at fasting state (t = 0 min) and 5 successive time points post-MMTT (t = 30, 60, 120, 180 and 240 min). At t = 0 ,1 and 2 h, the fingertip blood will be collected as well. Body composition will be measured by dual energy x-ray absorptiometry (DXA). All these samples will be used to the assessment of blood chemistry, metabolomics, single nucleotide polymorphism (SNP), gut microbiota etc.

Inclusion criteria

• healthy subjects: age 20-70 BMI ≥ 18.5 kg/m2
• Mets subjects:

age 30-70 BMI ≥ 18.5 kg/m2 and at least meet three of the following criterions(NCEP-ATPIII, for Asian Americans)

• Waist circumference ≥ 90 cm (men), ≥ 80 cm (women).
• Total triglyceride ≥ 1.7 mmol/L.
• HDL-c <1.03 mmol/L in men, <1.3 mmol/L in women.
• Systolic blood pressure ≥ 130 mmHg or diastolic blood pressure ≥ 85 mmHg.
• Fasting plasma glucose ≥ 5.6 mmol/L.

Exclusion criteria

• clinically diagnosed diabetes or use of anti-diabetic medications;
• clinically diagnosed cardiovascular, kidney, liver, pituitary, alimentary tract, and thyroid diseases, cancer(s), or mental illnesses;
• pregnancy or lactation;
• having gastrointestinal surgery within 1 year, excepting appendicitis or hernia;
• current use of antidepressant(s);
• alcohol consumption > 40 g/d or other substance abuse;
• severe diarrhea (watery stools ≥ 3 times/day ≥ 3 days or longer) in previous 3 months;
• participating any other studies within previous 3 months.