What is Green Tea for?
Green tea is a product made from the Camellia sinensis plant. It can be prepared as a beverage, which can have some health effects. Or an “extract” can be made from the leaves to use as medicine.
Green tea is used to improve mental alertness and thinking.
It is also used for weight loss and to treat stomach disorders, vomiting, diarrhea, headaches, bone loss (osteoporosis), and solid tumor cancers.
Some people use green tea to prevent various cancers, including breast cancer, prostate cancer, colon cancer, gastric cancer, lung cancer, solid tumor cancers and skin cancer related to exposure to sunlight. Some women use green tea to fight human papilloma virus (HPV), which can cause genital warts, the growth of abnormal cells in the cervix (cervical dysplasia), and cervical cancer.
Green tea is also used for Crohn’s disease, Parkinson’s disease, diseases of the heart and blood vessels, diabetes, low blood pressure, chronic fatigue syndrome (CFS), dental cavities (caries), kidney stones, and skin damage.
Instead of drinking green tea, some people apply green tea bags to their skin to soothe sunburn and prevent skin cancer due to sun exposure. Green tea bags are also used to decrease puffiness under the eyes, as a compress for tired eyes or headache, and to stop gums from bleeding after a tooth is pulled.
Green tea in candy is used for gum disease.
Green tea is used in an ointment for genital warts. Do not confuse green tea with oolong tea or black tea. Oolong tea and black tea are made from the same plant leaves used to make green tea, but they are prepared differently and have different medicinal effects. Green tea is not fermented at all. Oolong tea is partially fermented, and black tea is fully fermented.
What is Green Tea Possibly Effective for?
• Weight loss. Taking a specific green tea extract (EGCG) seems to help moderately overweight people lose weight. But green tea doesn’t help people keep the weight off.
• High blood pressure. Some research shows that drinking green tea regularly seems to lower the chance of getting high blood pressure. But not all research agrees.
• Stroke prevention. According to a large study done in Japan, drinking 3 cups of green tea per day seems to significantly lower the risk of having a stroke, compared to drinking one cup or no tea. Women seem to benefit more than men.
• Weak bones (osteoporosis). Population research suggests that drinking green tea for 10 years is associated with stronger bones.
• Type 2 diabetes. Drinking green tea may help prevent diabetes. Research suggests that Japanese adults who drink 6 or more cups per day of green tea have a 33% lower risk of developing type 2 diabetes compared to those who drink one cup per day or less. This is especially true for women.
• Breast cancer. Green tea does not seem to prevent breast cancer in Asian populations. However, in Asian-American populations, some evidence suggests that drinking green tea might reduce the risk of developing breast cancer. Most research on green tea for breast cancer has been in Asian populations. The effect of green tea on breast cancer risk in Western populations is less clear.
• Gum disease (gingivitis). Chewing candy that contains green tea extract seems to control plaque build-up on the teeth and reduce gum swelling.
• Prostate cancer. Chinese men who drink more green tea seem to have a lower risk of developing prostate cancer. The more tea they drink, the more their risk drops.
• Increasing mental alertness, due to the caffeine content of green tea.
• Chronic fatigue syndrome (CFS).
• Heart disease prevention.
• Kidney stones.
• Lung cancer.
• Stomach cancer.
• Skin cancer.
• Dental cavities.