1. Promote metabolism: Tea contains substances such as caffeine and tea polyphenols, which can stimulate the nervous system, promote metabolism and improve body function.

2. Protect the heart: Tea polyphenols and catechins in tea can reduce the contents of cholesterol and triglyceride, and reduce the occurrence of cardiovascular and cerebrovascular diseases.

3. Lowering blood sugar: Tea polyphenols in tea can lower blood sugar level, which has a certain auxiliary therapeutic effect on diabetic patients.

4. Antioxidant: Tea polyphenols in tea have a strong antioxidant effect, which can inhibit the generation of free radicals and slow down the aging of the body.

5. Health care: Tea polyphenols, catechins, amino acids and other components in tea help to enhance the body's immunity and maintain good health.

Disadvantages of drinking tea:

1. Affect iron absorption: Tannic acid in tea will combine with iron ions to form compounds that are not easily absorbed, which will affect the human body's absorption of iron.

2. Affect sleep: Caffeine in tea can stimulate the central nervous system, leading to insomnia, anxiety and other problems.

3. Affect digestion: Theophylline in tea stimulates the secretion of gastric juice, which will have adverse effects on people with gastrointestinal dysfunction.

4. affecting the absorption of vitamins: tea polyphenols and vitamin c in tea will interact and affect the absorption of vitamin C.

5. Damage to teeth: Acidic substances in tea will erode the surface of teeth, leading to acid plaque and dental caries.