Products
Green tea is available, for example, in tea stores, pharmacies, drugstores and grocery stores. Green tea originated in China and is consumed primarily in Asia. In Europe, black tea is more common.
Stem plant
The parent plant is the tea plant from the tea shrub family (Theaceae). It grows into an evergreen shrub or tree.
Medicinal drug
The young leaves of the tea plant are used as a medicinal raw material (Theae viridis folium, green tea leaves). Extracts are also made from the leaves. Unlike black tea, green tea is not fermented. The plant’s own enzymes, such as polyphenol oxidase, are inactivated with the help of steam. This changes the spectrum of the ingredients. Green tea contains more polyphenols (catechins) and black tea contains more aromatic substances.
Ingredients
- Methylxanthines: caffeine (about 10 to 50 mg per cup), theobromine, theophylline.
- Flavonoids, polyphenols, catechins (eg epicatechin, epicatechin-3-gallate, epigallocatechin, epigallocatechin gallate, EGCG), tannins.
- Amino acids, proteins, enzymes
- Aromatic substances, volatile compounds
- Minerals, vitamins
Effects
Green tea is believed to have various health-promoting effects. It has been shown in studies to have antioxidant, anti-inflammatory, anti-tumor, thermogenic and lipid-lowering properties, among others. Green tea has mild stimulant effects due to its caffeine.
Indications for use
Green tea is mainly consumed in the West as a health-promoting and mildly stimulating stimulant. An ointment containing green tea is approved as a drug for the treatment of genital warts; see Green Tea for Genital Warts.
Dosage
Green tea is prepared as an infusion. However, boiling water should not be used, but only 70 to a maximum of 90 °C. It is left to steep for only two to three minutes. Green tea can be infused two or three times.
Interactions
Tannins may inhibit the absorption of drugs, such as tricyclic antidepressants or neuroleptics.
Adverse effects
Possible adverse effects of the tea include indigestion. The caffeine may cause several side effects (see there). High-dose green tea extracts may exhibit liver-damaging properties, which are due to the catechins.
