Green tea is often touted as a wonder drink providing all sorts
of health benefits. Studies have shown that green tea can
prevent cancer, lower blood pressure, boost the immune system
and reduce hypertension. Although green tea gets the spotlight,
many of these same health benefits can be attributed to all
sorts of tea including oolong.
Tea is, after all, tea. The only difference between green,
oolong, and black tea is the way it has been processed after
harvesting. White tea is a little bit different because of the
way it is grown, but all tea is from the same plant - Camelia
sinensis. And this plant has naturally occurring antioxidants
that are beneficial to human health.
Antioxidants are also present in other types of food such as
nuts, fruits, vegetables, and wines. They are good for disease
prevention by combating free radicals - substances in the body
linked to cancer, Parkinson's disease, senile and drug-induced
deafness, schizophrenia, and Alzheimer's.
There are several components in tea that act as antioxidants
including catechins, flavanoids, and polyphenols.
White, Green or Oolong?
Oolong tea is produced by allowing the tea leaves to oxidize for
a short time after picking. Oxidation is the process which makes
the leaves turn dark on exposure to oxygen. Oolong is
semi-oxidized; black tea is fully oxidized; and green tea is
un-oxidized.
Fresh tea leaves are high in catechins. Processing the tea
reduces these levels, so the more the tea is oxidized the lower
the catechin levels. This means that white tea has the highest
levels of catechins closely followed by green tea.
Catechins are the media darling of green tea promoters and
usually receive the most coverage when discussing the health
benefits of tea. There is one point, however, which is often
overlooked: As the levels of catechins decrease during
oxidation, the levels of theaflavins and thearubigins increase.
These two substances are found in higher concentrations in
oolong and black tea than in green tea and have anti-allergy,
anti-inflammatory, and anti-cancer properties. A 2001 Chinese
study indicated that the antioxidant properties of green tea and
black tea are equal.
So it appears that oxidation does not eliminate the health
properties of tea, but simply reduces one type of antioxidant
while increasing other health-promoting compounds.
So is Oolong Good for You?
It is safe to say that all tea is good for you, but since we are
particularly interested in oolong, let's see what the medical
literature has to say.
*Diabetes - Oolong tea may be an effective adjunct to oral
hypoglycemic agents in the treatment of type 2 diabetes.
*Eczema - Japanese researchers reported that patients with a
form of eczema improved after drinking a liter of oolong tea
daily.
*Allergies - Two catechin derivatives (C-1 and C-2) with potent
antiallergic activity were isolated from Taiwanese oolong tea.
*Bacterial infections - Oolong tea polyphenols strongly
inhibited the enzyme activities of some types of streptococci.
*Cavities - Oolong tea polyphenolic compounds could be useful
for controlling dental caries.
*Obesity - Consumption of oolong tea stimulates both EE and fat
oxidation in normal weight men. *Cancer - Oolong tea extract has
a chemopreventive action against hepatocarcinogenesis.
Great stuff! Drinking oolong tea will make you healthier, live
longer, be more beautiful and have great teeth!
The Bottom Line
Drink oolong tea for your health, but don't lose sight of this
simple fact - people have been drinking tea for thousands of
years because it is a great tasting beverage. Sit back, relax,
and savour the sensations as you sip this wonderful drink. It's
good for the soul, and what's good for the soul is certainly
good for the body.
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References:
J. Agric. Food Chem., 47 (5), 1906 -1910, 1999.
10.1021/jf981114l S0021-8561(98)01114-5
Archives of Dermatology, January 2001
Diabetes Care 26:1714-1718, 2003
Appl Environ Microbiol. 1993 April; 59(4): 968973.
The American Society for Nutritional Sciences J. Nutr.
131:2848-2852, November 2001
Caries Res. 1993;27(2):124-9.
Jpn J Cancer Res. 1996 Oct;87(10):1034-8.
Journal of Nutrition. 2001;131:2248-2251.
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Copyright © 2006 by Ross MacIver TeaFromTaiwan.com
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