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Does
Bottled Green Tea Have Health Benefits, Too?
Have you ever wondered if bottled green tea has the same health
benefits as freshly brewed green tea? Well, sorry to break the news to
all of you bottled tea drinkers but in most cases, the answer appears to
be no.
In December 2006, the U.S. Department of Agriculture made public its
database on the flavonoid content of foods.1 (Flavonoids, a
type of polyphenol, are a group of compounds found primarily in fruits
and vegetables that act as powerful antioxidants. Green tea’s catechins
are a sub-group of the flavonoids.) The USDA list, which includes the
levels of catechins found in green tea that was prepared in different
ways, is a real eye-opener for those who drink bottled tea for health
reasons!
For example, the level of EGCg (green tea’s most potent catechin) in
brewed loose-leaf tea was 77.81 mg per 100 grams of infusion.
Decaffeinated green tea, however, had just one-third that amount,
weighing in at 26.05 mg. But ready-to-drink green tea (the kind that
comes in a can or a bottle) contained a minuscule 3.96 mg of EGCg, just
5 percent the amount found in freshly brewed green tea. And instant
green tea was even worse, with a practically nonexistent .5mg EGCg!
Similar studies measuring the health-promoting compounds in green tea
were done in 2005 by researchers at Oregon State University.2
They found that the polyphenol content and antioxidant activity in some
bottled tea products were 10 to 100 times lower than those found in
brewed tea!
Why does bottled (or canned) green tea have such low levels of
catechins? A major reason is that the catechins are sensitive to heat
and oxygen, making them easy to destroy during the processing,
transporting and storing of bottled tea. Also, many bottled tea products
are made from tea extracts, which have far fewer antioxidants to begin
with than brewed tea. Then, to make matters worse, bottled tea products
are often loaded with sugar or high fructose corn syrup which, besides
being unhealthy and unnecessary, can contribute to catechin breakdown.
If you still want to drink bottled green tea, be sure to look for a
high quality product made from brewed tea that contains no added
sweeteners and has the polyphenol or catechin content listed on the
label. Your best bet is a product that contains at least 75 mg
polyphenols or 50 mg EGCg per cup. If you can’t find one, how about just
settling for a nice bottle of water?
1http://www.nal.usda.gov/fnic/foodcomp/Data/Flav/Flav02-1.pdf
(Scroll to database pages 87-88)
2
http://oregonstate.edu/dept/ncs/newsarch/2005/Oct05/teaprotection.htm
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Nadine Taylor, M.S., R.D. presents
GreenTeaLibrary.com,
the most comprehensive collection of scientific information
describing the health benefits of green tea.
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