Next to water, green tea is one of the most popular beverages consumed worldwide. It has been used medicinally for centuries in India and China to remedy headaches, body aches and pains, digestion, depression, detoxification, as an energizer, to enhance immunity, and to prolong life.
Next to water, green tea is one of the most popular beverages consumed worldwide. It has been used medicinally for centuries in India and China to remedy headaches, body aches and pains, digestion, depression, detoxification, as an energizer, to enhance immunity, and to prolong life.
In recent years the popularity of green tea has been on the rise in North America as modern research has confirmed its numerous benefits for heart health, cancer protection, weight loss, and much more.
Green tea contains a number of beneficial compounds, including volatile oils, vitamins, minerals, caffeine, and potent antioxidants called polyphenols. Tannins, large polyphenol molecules, form the bulk of the active compounds in green tea, with catechins comprising nearly 90 percent. The main catechin, epigallocatechin gallate (EGCG), is more powerful as an antioxidant than vitamins C and E.
Studies have shown that green tea can offer protection against cardiovascular disease in several ways: it lowers total cholesterol levels and improves the cholesterol profile (the ratio of LDL cholesterol to HDL cholesterol). It also reduces platelet aggregation (prevents clotting) and lowers blood pressure. As well, the potent antioxidant properties of polyphenols help to reduce free radical damage to cells and prevent the oxidation of LDL cholesterol properties that inhibit the formation of atherosclerosis.
Cancer Preventer
The polyphenols in green tea have also been shown to reduce the risk of several types of cancer, including stomach, small intestine, pancreas, colon, lung, and breast cancer. These benefits may be attributed to green tea's ability to block the formation of cancer-causing compounds such as nitrosamines; suppress the activation of carcinogens; detoxify cancer-causing chemicals; inhibit growth of cancer cells; and stimulate apoptosis (programmed cell death).
Green tea also offers benefits for the immune system. It stimulates the production of several immune system cells and has antibacterial properties (even against the bacteria that cause dental plaque). Green tea also appears to be good for cancer patients undergoing radiation or chemotherapy by helping them maintain white blood cell count more effectively.
Weight Regulator
One area getting a lot of attention is green tea's benefits for weight loss. A study on mice, published in Cancer Research in July 1992, found that green tea reduced food intake, body weight gain, and fat tissue accumulation, as well as cholesterol and triglycerides levels. Levels of the hormone leptin (involved in fat storage) were also lower suggesting that green tea may have a direct effect on the regulation of body weight.
Studies in humans have shown that green tea can facilitate weight loss by increasing thermogenesis the rate at which the body burns calories. This was initially attributed to its caffeine content; however recent studies have shown that this is due to an interaction between its high content of catechin-polyphenols and caffeine.
Most studies documenting the health benefits of green tea have involved 3 to 10 cups (750 mL to 2.5L) per day. For those who don't drink tea, but want the benefits, tablets and capsules are available. Look for a product that is standardized for total polyphenol content and/or catechin concentrations. Most products provide 60- to 97-percent polyphenols and/or EGCG content.
No serious side effects are known, even with intakes as high as 20 cups per day. Since green tea contains some caffeine, higher doses may cause restlessness, insomnia, and tachycardia. Green tea can be decaffeinated; however this process may reduce the amount of beneficial phenolic/catechin compounds. Those taking blood-thinning medications, such as aspirin should be cautious because green tea can enhance the effect of the drug.
Sipping a cup of green tea is great medicine. It's also a good way to fight cancer and manage weight.