Helicobacter pylori is a common pathogen causing upper gastrointestinal diseases including gastric ulcer and gastric cancer. Recent epidemiological findings have also shown that it is also related to colon cancer, metabolic syndrome, gut dysbiosis, glycemic control and insulin resistance.

The aim of this study is to investigate whether the gut microbiota and insulin resistance of patients with H. pylori infection are abnormal. In addition, whether drinking fermented milk product with probiotic reduces Helicobacter pylori, improves gut microbiota, and increases butyrate-producing bacteria and insulin resistance.

Inclusion Criteria:

1. Age between 20 to 70 years old with positive Helicobacter pylori gastric C13 urea breath test (ΔUBT>10%).
2. Negative gastric Helicobacter (ΔUBT<2%) matching age, gender, and body mass index.

Exclusion Criteria:

1. Unhealthy habits or poor health status, including habitual smoking, alcoholism, polypharmacy or drug abuses.
2. Patients with acute diseases, such as respiratory tract infection, acute gastroenteritis.
3. In the past three months, those who have had dyspepsia but have not undergone gastroscopy, or have a history of active gastrointestinal ulcers and gastrointestinal bleeding.
4. Those who have had gastrointestinal cancer or have undergone gastrointestinal surgery.
5. Those who are unwilling to delay receiving Anti-H. pylori therapy.
6. Newly diagnosed cancer (except basal cell carcinoma) or cancer treatment in the past 5 years.
7. People who have had cardiovascular disease, respiratory disease, autoimmune disease, mental disease or other chronic diseases that are not well controlled, such as myocardial infarction or stroke, chronic obstructive pulmonary disease, inflammatory bowel disease, Schizophrenia.
8. Diabetes and those who are or need to take drugs.
9. Those who have used the following drugs in the past month: antibiotics, NSAIDs, obesity drugs, steroid therapy, proton pump inhibitors, bismuth agents.
10. In the past month, regularly consume the following foods (at least 2 times a week): probiotics, prebiotics, or any foods containing probiotics, dairy products (yogurt, cheese), Chinese medicine, kimchi, miso, honey, cranberry, spicy food.
11. Fecal occult blood positive, unexplained iron-deficiency anemia, weight increase or decrease by more than 5% within six months.
12. Abnormal liver function index (AST, ALT or ALP greater than 2 times the upper limit of normal), abnormal renal function index (eGFR less than 45 ml/min).
13. Pregnant or breast-feeding women.