The purpose of this study is to evaluate the efficacy and safety of hydrogen inhalation in type 2 diabetes patients.

The objective of the study is to evaluate the efficacy and safety of hydrogen inhalation compared with placebo in patients with type 2 diabetes mellitus after 12-week treatment in a randomized, double-blind, placebo-controlled design.

Inclusion Criteria:

1. Aged 18-75 years old and gender of both sex;
2. Body mass index 18.5kg/m2 to 40 kg/m2;
3. Diagnosed as type 2 diabetes according to the diagnostic criteria of type 2 diabetes established by WHO in 1999;
4. Patients with type 2 diabetes whose blood glucose is not well controlled after diet control and exercise therapy for more than 3 months;
5. HbA1c 7% to 10%, and fasting venous plasma glucose ≤ 15 mmol/L;
6. Be able to understand the procedures and methods of this clinical study, voluntarily participate in and sign the informed consent.

Exclusion Criteria:

1. Type 1 diabetes, gestational diabetes, or other specific types of diabetes;
2. Screening for having received anti-diabetic drug therapy within 3 months or receiving continuous anti-diabetic drug therapy at any time before screening for more than 3 months;
3. History of diabetic ketoacidosis, diabetic hyperglycemic hyperosmolar syndrome, lactic acidosis, diabetic hypoglycemia; or is currently combined with retinopathy, diabetic nephropathy and diabetic neuropathy;
4. Hyperlipidemia patients with irregular or unstable dose of lipid-lowering drugs
5. Chronic gastrointestinal disorders with obvious digestive and absorption disorders, as well as other endocrine diseases, such as hyperthyroidism, hypercortisolism, acromegaly, etc.;
6. Patients with diseases that may worsen due to intestinal flatulence (such as Roemheld syndrome, severe hernia, intestinal obstruction, intestinal surgery and intestinal ulcers);
7. Had transient ischemic attack, cerebrovascular accident or unstable angina in the past 6 months; History of myocardial infarction or had conducted coronary angioplasty or coronary artery bypass graft surgery; Heart failure (NYHA classification Stage III or IV), or left ventricular hypertrophy indicated by ECG;
8. Subjects (taking or not taking antihypertensive drugs) had poor blood pressure control (SBP ≥ 160mmhg, or DBP ≥ 100mmhg);
9. liver disease, ALT or AST > 2 ULN, or TBIL > 2 ULN, and the diagnosis was confirmed within one week;
10. Patients with renal function impairment (Cr > 1 ULN or Ccr < 60ml / min) and confirmed by reexamination within one week;
11. Had malignancy in the past 5 years, not including basal cell carcinoma;
12. History of acute or chronic pancreatitis, or related diseases that are most common cause of acute pancreatitis (such as recurrent cholelithiasis, etc.);
13. Combined use of drugs that affect glucose metabolism, such as glucocorticoids;
14. Combined use of Chinese herbal medicine with the effect of regulating blood glucose within 3 months;
15. Those who have serious diseases and may be in danger of life during treatment and follow-up;
16. Mental and neurological disorders, unable to correctly express their wishes;
17. Alcoholics and drug abusers and addicts;
18. Women of childbearing age are pregnant, breastfeeding, have pregnancy intentions or have a positive pregnancy test (urine HCG or blood HCG), and should not take effective contraceptive measures during the trial (effective contraceptive measures include sterilization, intrauterine device, oral contraceptive or diaphragm method prescribed by local law);
19. Patients who have participated in clinical trials of other drugs or medical devices in the past 3 months;
20. Patients with other diseases that the researchers believe will not be able to evaluate or are unlikely to complete the expected course of treatment and follow-up.