Green Tea and Cancer
Green tea has eclipsed the mark of an exotic Asian drink to a regular among grocery store shelves. Green tea is now an ordinary part of clinical research, with the goal of finding treatments for the heart, cancer and weight loss. The growth of alternative medicine in the United States and elsewhere has led to more interest in the medicinal properties of green tea. In particular, herbal remedies are becoming a greater interest among cancer patients, many of which are wondering if green tea may help. Further, many healthy individuals are thinking that green tea can offer a safer alternative to soft drinks with the additional bonus of cancer prevention.
Green tea has generated a buzz in regard to cancer prevention because it is often equilibrated to the healthy lifestyle of the Japanese. Japan has enjoyed lower rates of prostate and breast cancer and also less aggressive types of these cancers. Several factors may be involved in these occurrences, but does green tea help prevent and treat cancer? There is good reason to think that green tea may be helpful. Research has shown that green tea has significant antioxidant power [Source: Benzie et al]. Antioxidants are the nutrients needed to protect our cells from too much damage. Smoking in particular is a known risk factor for various types of cancer, and green tea has shown the ability to decrease the oxidative damage that occurs to the DNA when smoking [Source: Hakim]. Damage to DNA, the blueprints to all of our cells, is essentially a path to cancer.
Higher intake of green tea does seem to specifically protect against some types of cancer. A study compared the return of colon polyps, a potential precursor to colon cancer, in those taking a green tea supplement versus those who were not. Everyone in the study had previous polyps and was followed to see if green tea may prevent polyps from reoccurring. The supplement was taken daily. The green tea group showed significantly less number of recurring polyps and a substantial decrease in size if polyps did return [Source: Shimizu]. Green tea also appears to have a preventative nature for prostate cancer and seems to benefit those with precancerous changes in the prostate [Source: Bettuzzi]. Green tea seems to be beneficial in lowering the risk for more advanced prostate cancer [Source: Kurahashi]. Many men will be diagnosed with prostate cancer, with many more men having precancerous changes of the prostate cancer cells without any symptoms. Biopsies of men asked to drink green tea regularly demonstrate the nutrients of green tea find their way to the prostate, offering the opportunity for protection. Green tea may be a useful addition to help prevent prostate cancer cells from becoming more dangerous types of cancer.
Green tea may protect against other types of cancer as well. Regular consumption of green tea may help prevent breast cancer [Source: Sun]. Green tea has been used successfully as a topical agent and taken orally to treat genital warts [Source: Stockfleth, Ahn]. Green tea has also been shown to decrease the amount of viruses circulating in the body associated with the formation of adult T-cell leukemia [Source: Sonoda]. Green tea has been well-tolerated in research studies, with using doses of 7-8 cups of green tea, taken up to 3 times a day [Source: Laurie, Pisters].
Green tea is an ancient traditional beverage of Asia that now has many known health benefits, including its role in the prevention and adjunct treatment in many types of cancer. It is a well-tolerated and readily available addition to the diet. The tea offers a pleasant beverage that makes a good replacement to soft drinks, and may help the excess coffee intake that so many people indulge in each day. Green tea extract is also available in supplements, though ingredient levels will vary. Epigallocatechin gallate (EGCG) is one of the prominent nutrients in green tea. Supplements may contain 50 percent EGCG to denote that extract contains the nutrients needed for the benefits of green tea, with total dosage ranging from 100-200mg typically a day. Treatment dosages for cancer are done up to 3 times daily. It is best to ask a doctor versed in nutritional medicine to guide dosing, especially during cancer treatments.
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