Clinical Research Directory

Inclusion Criteria： 1. Male 2. Age 55-65; 18-28; 3. Able to understand and execute instructions; 4. After reading the consent form, be able to answer questions about the study and demonstrate understanding of the protocol; 5. Be able to participate in regular follow-up visits. Exclusion Criteria 1. Severe chronic or acute disease: cancer, clinically significant congestive heart failure, chronic obstructive pulmonary disease (COPD), previous or new-onset diabetes, inflammatory state, serum creatinine \>1.5 mg/dl , active liver disease, History of metabolic acidosis, poorly controlled hypertension, epilepsy, recent (within 3 months) cardiovascular events (MI, PTCA, CABG, stroke), severe renal insufficiency, inflammatory bowel disease, persistent glucocorticoids Treatment; neurological diseases such as dementia, AD, PD, etc.; infectious diseases such as HIV, hepatitis, tuberculosis, etc.; severe autoimmune diseases; 2. BMI\<18.5 or BMI\>30; 3. Persistent alcohol or drug abuse; 4. Treatment with drugs known to affect glucose metabolism (other diabetes drugs, systemic glucocorticoids, niacin); 5. Hypersensitivity to metformin or any component of the preparation; 6. Have taken metformin, low-dose aspirin, acarbose, vitamin C in the recent (3 months); 7. Unable to provide informed consent; 8. Other circumstances in which the researcher believes that the physical factors of the participants may adversely affect the research process or results.