International Scientific Symposium on Tea and Health – Part II
Last month’s newsletter generated a lot of positive energy, great comments and many questions from readers. We examined tea as it relates to diabetes, heart disease, cholesterol and weight loss. Additionally, we touched on tea’s beneficial properties; phytochemicals, flavonoids, polyphenols, and other specific tea antioxidants and how they work to fight the damage of free radicals.
Part II is dedicated to tea and cancer, highlighting the latest research. Tea flavonoids, thought to play a role in reducing the risk of cancer, seem to combat free radical damage, inhibiting uncontrolled cell growth (proliferation), boosting the immune system and promoting programmed cell death (apoptosis) helping the body ward off the development of cancer cells.
TEA AND CANCER
DNA and Immune Protection
DNA damage is implicated in the development of various types of cancer. Epigallocatechin gallate (EGCG) is believed to protect normal cells from cancer causing hazards and eliminate cancer cells through programmed cell death (apoptosis). Additional studies indicate further positive outcomes on the effect of tea on DNA and immune function.
- The potential anti-cancer benefits of green teas EGCG was tested on hamster cells and the results showed suppressed DNA changes and damage caused by carcinogens. Results indicated further protection from carcinogen damage and the inhibition of cancer cell growth and multiplication.
- An animal study indicated beneficial changes in immune function when black tea was ingested. The results showed that the black tea helped protect immune cells from cancerous cells, acting like anti-cancer drugs that aid in boosting the immune system without creating more cancer cells.
Teas impact on digestive cancers seems to be good. Numerous longer term, human trails have encouraging results, suggesting that tea may have an even greater impact then first thought. More research is needed but these preliminary findings are promising
- The University of North Carolina conducted an epidemiological* study on Russian women from Moscow. Researchers associated a 60% drop in the risk of rectal cancer in participants who consumed the equivalent of 2 ½ or more cups of tea per day when compared to participants who drank less than 1 ¼ cups. Women who drank 1 ¼ to 2 ½ cups per day showed a 52% decreased risk.
- Follow up from a previous study (NHANES I) shows tea drinkers had about a 42% reduction in the risk of colon cancer when compared to non tea drinkers. Furthermore men who drank more than 1 ½ cups of tea per day were found to have a 70% lower risk.
- A group of 34,000 healthy, postmenopausal women between the ages of 55 -69 were followed for 12 years. Researchers found that those consuming high levels of catechins, (a type of flavonoid found in tea, fruits and vegetables) had a 45% decrease in the incidence of rectal cancer. Tea catechins showed the strongest link to this decrease.
- Post-menopausal women, between the ages of 55 – 69 were followed for eight years in The Iowa Women’s Study. The data found that participants who drank 2 or more cups of tea per day had a 32 % and 60 % reduction in developing digestive and urinary tract cancers, respectively.
- Animals with colon cancer were studied at the University of South Carolina and were administered either water or green tea. Those given the green tea had a significant reduction in the development of new colon cancer tumors. This study suggests that green tea was effective in the early stages of development.
Existing research on teas preventative effects on prostate cancer in men was reviewed by researchers at the University of Wisconsin, Madison. Based on the review, which included epidemiological, in vitro and in vivo studies, the researchers suggest that tea, especially green tea, may be a good public health recommendation, possibly aiding in the prevention of prostate cancer.
Tea and Skin Cancer
It appears that both oral consumption and topical administration of tea may have beneficial effects when it comes to skin cancer. Various studies found the following results.
Scientist are gaining interest in and funding for further studies on the effects of tea on human health. More human trials are underway and additional studies are on the horizon. Many of the findings highlighted above are preliminary and only begin to scratch the surface of what lies ahead. Tea leaves, freshly brewed, possess significant levels of some of the most powerful antioxidants mother-nature provides us. Depending on how it is brewed, tea is low in caffeine. Further evidence strongly suggests that tea can ease the effects of tension and stress, a benefit we can all use more of especially as the holiday’s approach. I have yet to find any evidence that drinking tea is harmful, so why wouldn’t you increase your consumption, potentially warding off the damaging effects of living in our world today?
- A University of Arizona study conducted on participants who drank iced black tea and citrus peel found a 42% reduced risk of skin cancer. Check our new line of Citrus teas; Grapefruit Black Tea, Citrus Berry Splash Black Tea and the extremely popular Organic Lemon Ginger Green Tea.
- Hot black tea consumption is associated with a significantly lower risk of squamous cell carcinoma, a form of skin cancer. The potential protective effects are thought to be influenced by the strength, temperature and amount of time the tea is brewed.
- Topical application of green tea prior to UV exposure inhibited DNA damage or UV-induced skin cancer.
- Oral consumption of both green and black tea decreased the number of tumors in mice following UV radiation exposure.
Next month’s newsletter will further examine findings that were shared at the International Symposium.
© 2007 Teas Etc., Inc
ABOUT THE AUTHOR
Beth Johnston, a tea importer and noted tea expert, publishes an informative monthly newsletter on tea, tea history, health and lifestyle enhancements. To learn more about the world of tea, join her free newsletter at http://www.TeasEtc.com/Newsletter.asp
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