Green tea is made from the dried leaves of the same plant as traditional tea. However, traditional tea leaves are fermented, and green tea leaves are steamed but unfermented. Green tea may be brewed and drunk or ingested in tablet or capsule form. Green tea contains caffeine, but many extracts have been decaffeinated. It is high in flavonoids, polyphenols, and catechins. Those substances are antioxidants, often thought to protect cells from damage by oxygen, mutations, and cancer.
(See also Overview of Dietary Supplements.)
Madai ya Chai ya Kijani
People take green tea for many reasons, including prevention of cancer and coronary artery disease, as well as treatment of external genital warts. Other reasons are reduction of fat (lipid) levels in the blood, relief of osteoarthritis pain and menopausal symptoms, and enhancement of weight loss, memory, and longevity.
Ushahidi wa Chai ya Kijani
Few of the benefits claimed for green tea are supported by strong scientific evidence. However, topical green tea (applied directly on the wart) may help treat genital warts. Studies have also shown a small but significant loss of weight among users.
Athari Mbaya za Chai ya Kijani
Side effects are related to the effects (including the dose) of caffeine. They include insomnia, anxiety, rapid heart rate (tachycardia), and mild tremor. Pregnant women should avoid excessive amounts due to the caffeine content, because of the risk of miscarriage. Rare case reports document liver toxicity. Drinking brewed green tea on an empty stomach may increase the risk of liver injury, although this has not been adequately studied.
Mwingiliano wa Dawa na Chai ya Kijani
Vitamin K in green tea may decrease anticoagulant effects of warfarin, thus increasing the risk of blood clots.
Green tea may decrease blood levels of nadolol, a beta-blocker, as well as medications that help lower cholesterol levels (atorvastatin and rosuvastatin).
If green tea consumption is abruptly stopped, lithium blood levels may increase and lithium adverse effects may occur.
Green tea may also decrease absorption of iron and folic acid.
Mapendekezo ya Chai ya Kijani
Green tea is generally considered safe, although the health benefits, if any, are likely small. People should avoid drinking large amounts, especially if pregnant, and should avoid drinking green tea on an empty stomach.
Maelezo Zaidi
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
National Institutes of Health's National Center for Complementary and Integrative Health: Green Tea
