It's not everyone's
cup of tea - at least not yet -- but white
tea appears to have more potent anticancer qualities
than green tea, according to studies
performed at the Linus Pauling Institute of Oregon
State University in Corvallis.
The researchers tested the tea to determine whether it could
help prevent genetic mutations in
bacteria, and colon and rectal cancer in cancer-prone rats.
The rats were offered white tea -- at a
strength equivalent to steeping a tea bag in a cup for
5 minutes -- instead of water for 8 weeks. In
both experiments, white tea was shown to have a strong
protective effect, said Dr. Gilberto
Santana-Rios, who described his work at the national meeting
of the American Chemical Society. By some
measures, white tea offered twice the protection
of water alone, and significantly more protection than green
tea, he said.
``I was surprised by the potency. We were not expecting that
much of a good result,'' Santana-Rios told
Reuters Health. Although all teas are made
from the same type of plant, they differ in which parts
of the plant are collected and how they are processed.
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The most
common tea in North
America and much of Europe, black tea, is also the most heavily processed. For black tea the leaves are withered,
rolled, roasted and dried, and when
steeped they produce a characteristic dark
beverage.
For white tea, the
leaves and white-colored buds of the plant are merely steamed
and dried, leaving a mixture that looks like dried basil flecked
with small white buds. When
steeped in hot water, the result is a pale liquid with a taste reminiscent of green tea.
``We still don't know what it is about the white tea -- we
haven't found it yet,'' Santana-Rios
commented. But the researchers have ruled out the buds, which
are not used in other teas, by showing
that the leaves alone produce the identical effects. Santana-Rios suspects that processing destroys
certain anticancer substances found
naturally in the tea plant. Many of these chemicals have yet to
be discovered, but they
may include polyphenols, or catechins, which help give tea its
bitter taste. White tea also has more
caffeine than other teas, and caffeine is known
to have anticancer properties,
Santana-Rios pointed out.
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