Coffee is in the news again!
Coffee is in the news again! Remember when this beverage
used to be considered bad for your health? A current
study is now touting it as the beverage with the highest
'antioxidants' content based on the yet-to-be-published
results of a chemical analysis of its polyphenols. From the
information so far available (e.g., an
American Chemical Society abstract,
Associated Press,
National Geographic News), it appears that polyphenols
are being equated to antioxidants. But the antioxidant
strength of polyphenols (a huge class of chemicals)
varies widely. One polyphenolic compound can be 50 times
stronger in antioxidant activity than another. The study,
led by Joe A. Vinson, Ph.D., a chemistry professor at the
University of Scranton in Pennsylvania, apparently only
analyzed the amounts of polyphenols present in coffee and
other foods and drinks. No information regarding their
antioxidant activity is so far available. Frankly, I am not
surprised if coffee leads the ‘pack’ in polyphenols content
because for years it has been reported to contain up to 10%
chlorogenic acid, a common polyphenolic compound and
antioxidant widely present in plants. This compound is also
present in artichoke and honeysuckle in substantial amounts.
However, does its presence in coffee actually mean coffee
can provide you with the highest levels of antioxidants
needed to combat the toxic effects of free radicals in your
body? I wish we knew. But I am looking forward to reading
Dr. Vinson’s findings when he finally publishes them, which
I hope will include evidence to correlate the polyphenols
contents to their antioxidant properties.
Over the past decade, I have written frequently on the
irreproducibility of research results in the natural
products field due to scientists’ often lack of attention
paid to the test materials used in their studies. I hope
this is not such an example.
Reprinted here are two related articles published in 2000 in
Leung's Chinese Herb News, Issue 25, which explain
why you may not want to take the results of such research
too seriously, at least until botanical reference standards
such as
RBRMs™ are universally used to control more precisely
the identity and nature of the materials being studied.
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