Anti cancer function
Numerous studies suggest that green tea protects against a range of cancers, including lung, prostate and breast cancer. The reason cited is the antioxidant epigallo catechin gallate (EGCG), according to Hirofumi Tachibana's team at Kyushu University in Japan.
Their research showed that growth of human lung cancer cells that have a cell receptor called 67 LR is slowed significantly after drinking just two or three cups of green tea, which contains EGCG. The research also showed that 67 LR is involved in the propagation of prion diseases such as mad cow disease in humans. So knowledge of EGCG's effect on 67 LR might have implications in the treatment of these diseases.
According to the U.S. National Cancer Institute, in laboratory studies using animals, catechins inactivated oxidants before cell damage occurred, reduced the number and size of tumors, and inhibited the growth of cancer cells
Anti diabetes function
There is also epidemiological evidence that drinking green tea may help prevent diabetes although it is worth noting that this is evidence of an association, but that prospective studies are needed to confirm the effect.
Lowers stress hormone levels
According to a study by UCL researchers published in the journal Psychopharmacology, drinking black tea has an effect on stress hormone levels in the body and thus helps in recovering more quickly from life's stresses. The study showed that, 50 minutes after a high stress event, subjects who drank 4 cups of black tea per day for a 4 week period experienced an average cortisol drop of 47%, compared to 27% for the placebo group. Blood platelet activation, which is linked to blood clotting and the risk of heart attacks was also lower in the tea drinker's group
"herbal teas" and "herbal infusions"
Herbal "teas" contain no true tea leaves, but are created from an international collection of herbs and . These all-natural botanical ingredients are combined to create exciting flavors and aromas in a rainbow of colors from pale yellow to deep red.
Tea professionals and connoisseurs usually prefer to restrict the name 'tea' to real tea, so you may see the following names used as well:
• “Herbal infusion”, which simply means a drink made by steeping an herb in hot water. (Tea itself is an infusion of tea leaves.)
• “Tisane”, which in French means any herbal drink.
Some common herbs that are used as tisanes are peppermint, chamomile, rose hips, lemon verbena, and fennel. A number of companies specialize in producing herbal blends. Many tea companies also sell tisanes.
Some exaggerated claims have been made for the medicinal properties of herbal infusions. Even so, some herbs do have generally recognized benefits. For instance, rose hips contain vitamin C; chamomile helps many people relax; and peppermint has a noticeable soothing effect on the stomach. Herbs can also cause problems. Chamomile, for example, can cause allergic reactions in people who are allergic to ragweed.