Revisiting the French Paradox
Not
quite the solution to the french paradox.
Just before Christmas 2OO1,
the research group led by Roger Corder, PhD, at the William
Harvey Research Institute in London, stimulated a flurry of
excitement by publishing a brief communication in nature.
proposing an explanation of the French paradox and of the
mechanism by which red wine reduces the risk of coronary
heart disease, the major killer and disabler of the
developed world.
Calling endothelin-1, a
peptide (protein building block) produced in blood vessels,
“crucial in the development of coronary atherosclerosis,”
the Corder group found that a component of red wine
suppressed the elaboration of endothelin-1. Endothelin-1 is
a powerful constrictor of blood vessels, thereby bad for
their health. The prudent took note with interest, but
hedged their bets. Corder, who qualified as a pharmacist in
1978, has pursued a career in research. He is now professor
of experimental therapeutics. He and his colleagues
published another brief communication in nature in November,
2OO6, in which the previously unknown inhibitor of
endothelin-1, and therefore of coronary and other
blood-vessel atherosclerosis, is identified as a group of
polyphenols, procyanidins, mainly derived from grape seeds.
They are also found in chocolate, apples, cranberries, and
some other fruits, nuts and spices. They are almost absent
from grape juice, except Concord. Pomegranates contain a
different, but still beneficial, polyphenol.
Corder believes that
procyanidins (which are not antioxidants) are the prime
healthful components of wine, chiefly functioning by
counteracting the adverse effects of endothelin-1. As
supporting evidence, he cites the relatively high proportion
of people surviving to advanced age in locales producing
wines containing abundant procyanidins: parts of
southwestern France, Sardinia, Crete, and the former Soviet
Republic of Georgia. In his new book, The Red Wine Diet
(Avery, 2OO7), he seems to disdain the widely accepted
contributions to health of the antioxidant polyphenols,
including resveratrol, and of alcohol, and scorns modern
soft, fruity, “easy-to-drink” wines low in polyphenols,
especially those low in procyanidins.
Some grape varieties are
particular rich in procyanidins, for example, the tannat of
southwestern France. (Maybe that’s why I’ve always liked
Madiran). Vineyard features cited as favoring high
procyanidin concentration include high altitude, infertile
soil, mature vines, avoidance of excess water, long, slow
ripening, optimal sun and heat, cool nights, low yield, sea
breeze, fog. In the winery, there should be long skin and
seed contact during fermentation, and minimization of fining
and filtering. Of course, much of this is simply a recipe
for producing good wine. Man’s manipulations can obliterate
the effects of most of these. Corder has concluded that the
traditional winemaking preserved in the areas of high
longevity, including the just-cited factors, is responsible
for the long survivals, by means of the abundance of
procyanidins.
The work of Corder’s group
is intriguing, but controversial. Neither methods of
investigation nor the inferences drawn can be said at this
stage to stand up unsupported as established science. And we
have to account for the effects of alcohol and of the
antioxidant polyphenols, both demonstrated as multifaceted
enhancers of health. Once we are more certain of the role of
the procyanidins, we can hope to integrate their actions
into our still incomplete understanding of the formation of
and protection from atherosclerotic disease of the
coronaries and other arteries, not only with reference to
drinking.
