Tuesday, July 21, 2009

White Tea vs. Green Tea

When discussing white tea vs green tea, it is important to realize that they both come from the same plant, the tea plant Camellia sinensis. The main difference between the two types of tea is that the white tea leaves are harvested at a younger age than the green tea leaves. They both undergo very little processing. White tea is not fermented at all, while green tea is partly fermented. By contrast, black tea is fully fermented. Because they are so gently treated, white tea and green tea retain their content of beneficial antioxidants.

Antioxidants

However, studies have shown that the young, white tea leaves retain antioxidants in higher concentrations than green tea does. Studies have shown that white tea has a concentration of antioxidants that is three times higher than in green tea. Essentially, white tea contains the same concentrations of antioxidants as the young and fresh tea leaf buds that are still attached to the bush. This makes white tea the tea with the highest antioxidant content, which for many is the main reason for drinking white tea. For comparison, one cup of white tea contains approximately twelve (12) times as much antioxidants as fresh orange juice.

Caffeine

White tea contains less caffeine than green tea, about 15 mg per serving compared to the 20 mg for green tea. If caffeine tends to make you jittery, white tea may be the better choice.

Studies of white tea:

1. "Past studies have shown that green tea stimulates the immune system to fight disease," says Milton Schiffenbauer, Ph.D., a microbiologist and professor in the Department of Biology at Pace University's Dyson College of Arts & Sciences and primary author of the research. "Our research shows White Tea Extract can actually destroy in vitro the organisms that cause disease. Study after study with tea extract proves that it has many healing properties. This is not an old wives tale, it's a fact."

White tea was more effective than green tea at inactivating bacterial viruses. Results obtained with the bacterial virus, a model system; suggest that WTE may have an anti-viral effect on human pathogenic viruses. The addition of White Tea Extract to various toothpastes enhanced the anti-microbial effect of these oral agents.

Studies have also indicated that WTE has an anti-fungal effect on Penicillium chrysogenum and Saccharomyces cerevisiae. In the presence of WTE, Penicillium spores and Saccharomyces cerevisiae yeast cells were totally inactivated. It is suggested that WTE may have an anti-fungal effect on pathogenic fungi.

Several findings in the new study are of particular interest:
* The anti-viral and anti-bacterial effect of white tea (Stash and Templar brands) is greater than that of green tea.
* The anti-viral and anti-bacterial effect of several toothpastes including Aim, Aquafresh, Colgate, Crest and Orajel was enhanced by the addition of white tea extract.
* White tea extract exhibited an anti-fungal effect on both Penicillium chrysogenum and Saccharomyces cerevisiae.
• White tea extract may have application in the inactivation of pathogenic human microbes, i.e., bacteria, viruses, and fungi.

2. Possible anti-obesity effects of white tea have been demonstrated in a series of experiments on human fat cells (adipocytes). Researchers have now shown that an extract of the herbal brew effectively inhibits the generation of new adipocytes and stimulates fat mobilization from mature fat cells.

Marc Winnefeld led a team of researchers from Beiersdorf AG, Germany, who studied the biological effects of an extract of white tea – the least processed version of the tea plant Camellia sinensis. He said, "In the industrialized countries, the rising incidence of obesity-associated disorders including cardiovascular diseases and diabetes constitutes a growing problem. We've shown that white tea may be an ideal natural source of slimming substances".

After treating lab-cultured human pre-adipocytes with the tea extract, the authors found that fat incorporation during the genesis of new adipocytes was reduced. According to Winnefeld, "The extract solution induced a decrease in the expression of genes associated with the growth of new fat cells, while also prompting existing adipocytes to break down the fat they contain".

White tea is made from the buds and first leaves of the plant used to make green tea and the black tea most commonly drunk in Western countries. It is less processed than the other teas and contains more of the ingredients thought to be active on human cells, such as methylxanthines (like caffeine) and epigallocatechin-3-gallate (EGCG) – which the authors believe to be responsible for many of the anti-adipogenic effects demonstrated in their study.