The antioxidant power of coffee by bestt571

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									The antioxidant power of coffee
Coffee is the largest source of antioxidants in the typical American's diet,
according to an article, published in January in Buffalo News newspaper that also
describes its benefits on the human brain, possibly lowering the risk for
Alzheimer's and Parkinson's disease as well as offering a measure of some
cancer protection.

The publication quotes a 2005 study by a University of Scranton team of
researchers led by Joe Vinson, Ph.D., Professor of Chemistry who says that
while coffee is the primary source of antioxidants in the American diet, it is not
necessarily the best source - dates, cranberries and red grapes have high
concentrations of antioxidants, although Americans don’t consume much of these
foods.

According to the American National Coffee Association, more than 80% of U.S.
adults consume coffee at least occasionally, while more than half drink it on a
daily basis.

Antioxidants are valuable bioactive agents that quench damaging free radicals
inside the body (unstable molecules that can cause damage to cells and DNA).
They also help to boost immune systems and have a number of potential health
benefits.

While the body produces its own antioxidants, it also gets a wide variety of
antioxidants from the food and drinks – fruits and vegetables being the main
sources. Vitamins C and E are well known antioxidants, but there are numerous
others.

According to the International Food Information Council (IFIC), the various
antioxidants in foods help stop free radicals, which may help reduce the risk of
some cancers, cognitive impairment, arthritis, immune dysfunction and
cardiovascular diseases.

Coffee is sixth among the top 50 antioxidant-containing foods, according to a
publication in American Journal of Clinical Nutrition. The rankings were based on
the amount of antioxidants found in a typical serving size. For a typical coffee,
that's about 170.5 ml (6 ounces). Only blackberries, walnuts, strawberries,
artichokes and cranberries contained more antioxidants per serving than did
coffee.

According to the French researcher Astrid Nehlig who specialises in coffee-
health interaction at the French National Institute of Health and Medical
Research (INSERM), coffee contains chlorogenic acids, known as potent
antioxidants.




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During the past years, consumers have begun incorporating antioxidant rich
foods into their diets to decrease risk for disease and to delay the onset of many
age-related conditions. According to the US-based Institute of Food
Technologists, sales of products carrying an antioxidant claim jumped nearly
20% in the US during 2005. One of every four consumers says they eat fruits or
vegetables to prevent disease, one in three eats them to feel healthy, and nearly
nine of ten eat them to stay healthy.

According to the results of a study by L. F. Andersen and colleagues of the
University of Oslo, published in 2006 in the American Journal of Clinical Nutrition,
"consumption of coffee, a major source of dietary antioxidants, may inhibit
inflammation and thereby reduce the risk of cardiovascular and other
inflammatory diseases in postmenopausal women”.

A previous Norwegian study, published in 2004, found that coffee (average daily
intake about 480 ml) was the major contributor to the total intake of antioxidants
(about 66%) in Norwegians’ diet. Chlorogenic acid (the ester of caffeic acid with
quinic acid), the most abundant polyphenol in coffee, is likely responsible for a
substantial part of coffee antioxidants.

Green and black coffee beans contain 15.9 and 22.6 mmol total antioxidants in
100 g, respectively. This difference between green and black coffee beans
agrees with previous data showing that although some antioxidants tend to be
damaged during the roasting process, other are formed in so-called Maillard
reactions (the browning reaction).

Of the noncoffee total antioxidant intake, fruits (including berries), tea, cereals,
wine, and vegetables contributed respectively about 26, 25, 13, 10, and 6% of
total antioxidants. Dietary beta-carotene, alpha-tocopherol, and vitamin C
contributed only 0.1, 0.3, and 8.5%, respectively, of the total intake of
antioxidants. Of the noncoffee total antioxidant intake, beta-carotene, alpha-
tocopherol, and vitamin C together contributed 24%.

A major issue is whether the antioxidants from coffee are bioavailable and
bioactive. Several studies demonstrated bioactivity of coffee that support coffee’s
contribution to antioxidant defence. Many epidemiologic studies found that coffee
is associated with reduced plasma gamma-glutamyl transpeptidase, a suggested
biomarker for early oxidative stress.

Furthermore, coffee is protective in models of experimental carcinogenesis and is
associated with reduced incidence of human colorectal cancer, gallstone,
Alzheimer's and Parkinson's disease, liver cirrhosis, and type 2 diabetes in
epidemiologic studies. The observation of a significant contribution of coffee to
the total intake of antioxidants suggests a possible mechanism behind these
potentially beneficial effects of coffee.




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Moderate coffee consumption may thus have health benefits in complement to a
diversified and balanced diet. As coffee is a very complex product, compounds
other than antioxidants may also play a role in the physiological effects of coffee.

Infonicks, January 2007

References:
McAllister R. Coffee has its benefits. 9 January 2007. Buffalo News www.buffalonews.com
Scranton professor’s study cites antioxidant benefits of coffee
http://matrix.scranton.edu/pdf/journal_fall_2005.pdf
Bakalar N. Coffee as a health drink? Studies find some benefits. 15 August 2006 The New York
Times www.nytimes.com
Svilaas A., Sakhi A., Andersen L., Svilaas T., Ström E., Jacobs D., Ose L. and Blomhoff R.
Intakes of antioxidants in coffee, wine, and vegetables are correlated with plasma carotenoids in
humans. The Journal of Nutrition. 134:562-567, March 2004
http://jn.nutrition.org/cgi/content/abstract/134/3/562
Andersen L. et al. Consumption of coffee is associated with reduced risk of death attributed to
inflammatory and cardiovascular diseases in the Iowa Women's Health Study. Am J Clin Nutr,
2006;83(5):1039-1046) www.ajcn.org
International Food Information Council www.ific.org
French National Institute of Health and Medical Research www.inserm.fr/en/home.html
Institute of Food Technologists www.ift.org




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