What's All the Hype About?
High tea, tea ceremonies, green tea, black tea, aromatherapy tea baths, tealeaf readings, teahouses, dessert tea... You've no doubt heard of the many health benefits of green tea. Green tea shampoos and skin care products are even being promoted! What's all the hype about?
A common drink in the Eastern world for centuries, green tea's popularity is only recently rising in the Western world. What they've instinctively known for hundreds of years, we are only beginning to discover: there's something magical about sitting down with a cup of tea and sipping away at the brew that relaxes the tension and eases the mind.
but it's not just recent hype. It's knowledge that's been growing for centuries. The ancients say it all started 2735 B.C. when a leaf from the camellia sinensis tree, the tea plant, blew into a cup of boiled water belonging to Chinese Emperor Shen Nung.
The rest is culinary history.....
Health Benefits Favored for Continuous History
"Tea" is from the leaves of the camellia sinensis plant. There are three types of tea: Green, Oolong and Black. They are categorized according to their oxidation levels (called the fermentation process).
Green Tea is steamed, baked or pan heated to prevent oxidation and thus, the leaves remain green
Oolong Tea is partially fermented. Oxidation is cut short so the leaves are black only on the edges.
Black Tea is fully fermented, producing black leaves.
So why is green tea getting all the attention in the science world? It's mainly because of the antioxidant epigalloctechin-3 gallate (EGCG) that is preserved in green tea, but lost in oolong tea and black tea when fermented. Antioxidants are thought to prevent free radicals, which are incomplete cells that attack healthy cells, causing damage that can lead to certain diseases, especially cancer and heart disease.
"The Highest Amount of Any Known Antioxidant is Found in Green Tea"
A Study conducted in September of 1997 by Dr. Lester Mitscher at the University of KAnsas concluded that the highest amount of any known antioxidant is found in green tea. Compared to other known antioxidants, EGCG was found to be 100 times more effective than vitamin C, 25 times more effective than Vitamin E and twice as powerful as resveratrol (in red wine) at neutralizing free radicals, which may explain why the rate of heart disease among Japanese men is quite low, even though approximately seventy percent are smokers.
How Does Green Tea Work?
the extract EGCG in green tea mentioned earlier in this brochure has been found to protect against a range of cancers, including lung, protect and breast cancer but the mechanism behind this is just beginning to be understood...
A research team at Kyusyu University in Japan report that EGCG inhibits tumour cell growth by binding to a receptor on cells called the 67-kDa laminin receptor. A variety of tumors produce abnormally high levels of 67 LR, and the receptor is thought to be involved in the spread of cancers through the body.
Writing in the online edition of Nature Structural and Moleculat Biology, the researchers showed that the growth of human lung cancer cells that have the receptor slows significantly when they are exposed to EGCG at the concentrations reached in the body after drinking just two or three cups of green tea.
A report on the research by Nature notes that other studies have suggested that the 67 LR receptor is involved in the propagation of prion diseases such as Creutzfeld-Jacob Disease. The Japanese team believe that finding out how EGCG acts on 67 LR might have implications for treating prion diseases, we well as leading to new anti-cancer strategies.
Green Tea Consumption and Cognitive Function
Although considerable experimental and animal evidence showed that green tea may possess potent activities of neuroprotection, neuro-rescue, and amyloid precursor protein processing that may lead to cognitive enhancement, no human data were available until researchers at the Tohoku University Graduate School of Medicine, Sendai, Japan analyzed cross-sectional data from a community-based Comprehensive Geriatric Assessment (CGA) conducted in 2002.
1003 Japanese subjects, aged ≥ 70 completed a self-administered questionnaire that included questions about the frequency of green tea consumption.
The object was to examine the association between green tea consumption and cognitive function in humans.
Researchers analyzed cognitive function by using the Mini-Mental State Examination with cutoffs of <28, <26, and <24 and calculated multivariate-adjusted Odds Ratios (ORs) of cognitive impairment.
The Results showed higher consumption of green tea was associated with a lower prevalence of Cognitive Impairment (CI). At the <26 cutoff, after, adjustment for potential confounders, the ORs for the cognitive impairment associated with different frequencies of green tea consumption were:
1.00 (reference) for ≤3 cups/week
0.62 (95% CI: 0.33, 1.19) for 4-6 cups/week
0.46 (95% CI: 0.30, 0.72) for ≥ 2 cups/day
Corresponding ORs for black or Oolong tea were:
1.00 (reference) Corresponding ORs for
0.60 (95% CI: 0.35, 1.02) for 4-6 cups/week
0.87 (95% CI: 0.55, 1.38) for ≥ 2 cups/day
Corresponding ORs for Coffee were
1.00 (reference) Corresponding ORs for
1.16 (95% CI: 0.78, 1.73) for 4-6 cups/week
1.03 (95% CI: 0.59, 1.80) for ≥ 2 cups/day
The results were essentially the same at cutoffs of <28 and <24.
Conclusion: A higher consumption of green tea is associated with lower prevalence of cognitive impairment in humans.
New evidence is emerging that green tea can even help dieters. In November, 1999, the American Journal of Clinical Nutrition published the results of a study at the University of Geneva in Switzerland. Researchers found that men who were given a combination of caffeine and green tea extract burned more calories than those given only caffeine or a placebo.
Citizens of Uji and Shizuoka, where most green tea in Japan is harvested, have among the lowest rates of cancer in the world. They drink more high quality green tea, per capita, than residents of any other region in Japan.
Green tea can even help prevent tooth decay. Just as its Bacteria-destorying abilities can help prevent food poisoning, it can also kill the bacteria that causes dental plaque.
Green tea contains less caffeine than coffee: there are approximately thirty to sixty mg. of caffeine in eight ounces of green tea, compared to over-hundred mg. in eight ounces of coffee.
A controlled trial in 240 men and women that went on for 12 weeks found that the green tea group had significant decreases in body fat percentage, body weight, waist circumference and abdominal fat.