Green tea's popularity with the health-conscious population has risen dramatically during the last 5 years,
and with good reason. Extensive research with green tea's
active constituents has shown it to be effective for weight loss and to possess anti-mutagenic,
anti-bacterial, and anti-cancer properties. These benefits come specifically from compounds in green tea
that reduce oxidative stress, called bioflavonoids.
Researchers have found green tea to be an excellent source of a potent, bioflavonoid-rich
compound that's high in polyphenols — a special class of bioflavonoids. The most important of the
polyphenols in green tea are the catechins — and in particular, Epigallocatechin
Gallate (EGCG), a very strong antioxidant.
The phenol groups in tea polyphenols are extremely active — easily able to capture and neutralize
free radicals and other pro-oxidants. Researchers have found that EGCG is over 200 times more
powerful than vitamin E in neutralizing pro-oxidants and free radicals that attack lipids (oils
and fats.) EGCG is also 20 times more potent than vitamin E in reducing formation of the dangerous
and potentially mutagenic peroxides that form in rancid fats and lard.
The polyphenol, EGCG, also offers protection against food poisoning, respiratory and digestive infections,
while encouraging acidophilus growth, and regularizing bowel habits. In laboratory
studies, 500 mg. of green tea catechins per day have even been shown to significantly lower
blood pressure and possess anti-mutagenic activity. Additionally, at very high levels (0.5% to
1% of daily diet) green tea catechins reduced high total- and LDL-cholesterol levels.
All this said, it's easy to see why green tea is a valuable tool for maintaining health... but what
about the newcomer in the tea aisle? Is there validity in all the hype about white tea?
Absolutely. While these amazing polyphenols are highly present in green tea, they exist in
even larger concentrations in white tea! You see, green tea's fermentation process reduces the
amount of these beneficial compounds. But white tea has an advantage here...
Instead of air-drying and
fermenting like green tea, the white tea leaves are merely steamed. White tea has no
fermentation process, and is made from immature tea leaves that are picked shortly before the
buds have fully opened. White tea takes its name from the silver fuzz that still covers the buds,
which turns white when the tea is dried. Larger amounts of EGCG can help
people to lose weight more effectively, giving white tea the potential to be a future blockbuster
ingredient. EGCG is a clinically proven stimulator of thermogenesis — a process that is
critical to weight loss.
Thermogenesis is the generation of heat by physiological processes. In our bodies, it occurs in
part through a series of chemical reactions in which fat molecules are "burned" to form carbon
dioxide and water. These reactions liberate thermal energy (heat), which, along with the carbon
dioxide and water, is tangible evidence of the disappearance of those fat molecules. Thermal
energy is measured in units of calories. By stimulating thermogenesis, EGCG contributes to your
body's caloric output. Hence, energy expenditure is increased, and weight loss is the result.
In a research study at the University of Switzerland, subjects consuming 270 mg of EGCG per day
produced a four percent increase in energy expenditure (considered to be a significant amount.)
This corresponds to a large increase in the thermogenic component of total energy expenditure:
about 35 to 43%. Although this study was completed with Green Tea, we can only imagine the results
of using white tea with its higher EGCG content, producing even more effective weight loss.
In fact, Scientists at the University of Chicago's Tang Center for Herbal Medicine Research have
found that EGCG caused rats to lose up to 21 percent of their body weight. Rats injected with
epigallocatechin gallate (EGCG) lost their appetites and consumed up to 60 percent less food after
seven days of daily injections.
Shutsung Liao, PhD, Director of the Tang Center and professor in the Ben May Institute for
Cancer Research and colleagues to study the effects of EGCG on the endocrine systems of rats
found that EGCG has also been shown to affect appetite reducing leptin levels.
Leptin is a protein produced by fats that appear to play an important role in how the body
manages fat storage through brain signals. In the March 2000 issue of Endocrinology, Liao
reported that rats injected with EGCG for just a few days experienced significant changes in
the blood levels of several hormones, including leptin. "This result was significant because
previous research has shown that leptin is involved in controlling the appetite," says Liao,
"but the result was very unexpected."
When Liao injected normal rats with EGCG, their leptin levels in the bloodstream went down.
This should have caused the rats to eat more. Instead, they ate less. Next, Liao injected rats whose
leptin receptors had been desensitized. These rats were engineered
to be immune to changes in leptin concentration. When these leptin-numb rats were injected with
EGCG, the results were the same: the rats ate less.
EGCG's reputation for weight loss becomes even more prevalent due to it's reported beneficial
effects on insulin and blood sugar. The authors of a 2002 EGCG study (Anderson RA, Polansky MM.
Tea enhances insulin activity J Agric Food Chem 2002;50:7182-6) cited other research in which
the antidiabetic effects of tea on human beings were investigated. When humans in clinical
trials ingested tea EGCG catechins before ingesting 50 g of starch (which is converted to
glucose by digestive enzymes, mainly alpha-amylase), glucose production was suppressed, apparently
because the catechins inhibited the enzyme action.
It has also been found that the uptake of glucose by the intestine for transfer to the bloodstream
is markedly suppressed by EGCG. This suppression would be strongest with EGCG compounds in white
tea that are the most active in enhancing insulin activity, decreasing insulin resistance and
promoting weight loss.
Typical research has shown that consuming 100-500 mg a day of EGCG (10 cups of green tea or
6 cups of white tea) can produce all of the benefits explained above.
Scientists are finding that not only does white tea contain more EGCG
than green tea, but that it also may contain different catechin profiles that possess even
greater benefits than ones from green tea. A good variety of white tea
is called "silver needles." This highly prized Silver Needles white tea is made only from tender
new buds that are covered in silver-white hairs. The leaves are picked only two days a year in
the early spring and are processed entirely by hand. When infused, Silver Needles produces a
clear, straw colored tea with an extraordinary full-bodied, fresh and sweet taste.
Chief Science Officer, DynaPure Nutrition
Copyright © June 2005 Pete Maletto and Low Carb Luxury