Typically, I compile my own information. However, I think they did a fantastic job.
There are three main varieties of tea from Camellia sinensis — green, black, and oolong. The difference between the teas is in their processing. Green tea is made from unfermented leaves and reportedly contains the highest concentration of powerful antioxidants called polyphenols.
Atherosclerosis – population based studies support that it may help prevent atherosclerosis. The FDA has rejected this claim stating that there is no credible evidence.
Cholesterol Research shows that green tea lowers total cholesterol and raises HDL (“good”) cholesterol in both animals and people. One population-based clinical study found that men who drink green tea are more likely to have lower total cholesterol than those who do not drink green tea. Results from one animal study suggest that polyphenols in green tea may block the intestinal absorption of cholesterol and promote its excretion from the body. In another small study of male smokers, researchers found that green tea significantly reduced blood levels of harmful LDL cholesterol.
Gastrointestinal Green tea may help reduce inflammation associated with Crohn’s disease and ulcerative colitis, the two types of IBD. If green tea proves to be helpful for preventing colon cancer, this would be an added benefit for those with IBD because they are at risk for colon cancer.
Diabetes Green tea has been used traditionally to control blood sugar. Animal studies suggest that green tea may help prevent the development of type 1 diabetes and slow the progression once it has developed. A few small clinical studies have found that daily supplementation of the diet with green tea-extract powder lowered the hemoglobin A1c level in individuals with borderline diabetes.
Liver disease Population-based clinical studies have shown that men who drink more than 10 cups of green tea per day are less likely to develop disorders of the liver. Green tea also seems to protect the liver from the damaging effects of toxic substances such as alcohol. Animal studies have shown that green tea helps protect against the development of liver tumors in mice. Results from several animal and human studies suggest that one of the polyphenols present in green tea, known as catechin, may help treat viral hepatitis (inflammation of the liver from a virus). In these studies, catechin was isolated from green tea and used in very high concentrations. It is not clear whether green tea (which contains a lower concentration of catechins) confers these same benefits to people with hepatitis.
Weight loss green tea extract may boost metabolism and help burn fat. One study confirmed that the combination of green tea and caffeine improved weight loss and maintenance in overweight and moderately obese individuals. Some researchers speculate that substances in green tea known as polyphenols, specifically the catechins, are responsible for the herb’s fat-burning effect.
Other uses Drinking green tea has been found effective in a small clinical study for dental caries, or tooth decay. More studies need to be performed. Green tea may also be useful in inflammatory diseases, such as arthritis. Research indicates that green tea may benefit arthritis by reducing inflammation and slowing cartilage breakdown. Chemicals found in green tea may also be effective in treating genital warts and preventing symptoms of colds and influenza.
Composition Polyphenols contained in teas are classified as catechins. Green tea contains six primary catechin compounds: catechin, gallaogatechin, epicatechin, epigallocatechin, epicatechin gallate, and apigallocatechin gallate (also known as EGCG). EGCG is the most studied polyphenol component in green tea and the most active. Green tea also contains alkaloids including caffeine, theobromine, and theophylline. These alkaloids provide green tea’s stimulant effects. L-theanine, an amino acid compound found in green tea, has been studied for its calming effects on the nervous system.Most green tea dietary supplements are sold as dried leaf tea in capsule form. Standardized extracts of green tea are preferred. There are also liquid extracts made from the leaves and leaf buds. The average cup of green tea contains between 50 – 150 mg polyphenols (antioxidants). Decaffeinated green tea products contain concentrated polyphenols. Caffeine-free supplements are available.
Green Tea contains Vitamin K.