In the eyes of science all alcoholic beverages are created equal,
however, some drinks may be more equal than others. Red wine may
be one of those beverages offering a dual action of alcohol and
antioxidants. The name of the game is Red Wine Polyphenols (RWP)
- compounds derived from grape tannins and anthocyanin pigments
that belong to the most powerful antioxidants in the world. As
we absorb polyphenols, they change the properties of blood lipids
making LDL-cholesterol more resistant to the sort of oxidation
that can trigger atherosclerosis and coronary heart disease.
From Coronary Heart Disease to Cancer
For many years the overwhelming evidence that light-to-moderate
alcohol use lowers the risk of coronary heart disease has been
in focus. In 2000 Morten Grønbæk with a study of data from 257,859
person-years of follow-up (the Copenhagen Centre for Population
Studies) was able to conclude that not only did wine drinkers
have significantly lower mortality from coronary heart disease;
with a consumption of 1-3 glasses a day wine drinkers also reduced
their risk of cancer by 20 percent compared with non-drinkers.
As the number of global cancer deaths are rising there is an urgent
need of efficient methods of cancer prevention and cancer cure.
Earlier studies have found a strong protective effect of intake
of fruits and vegetables against cancer. The potential role of
red wine polyphenols in cancer prevention may turn out to be one
of the most exciting areas of current cancer research.
RWP in cancer prevention
In 2000 Elias Castanas, professor of experimental endocrinology
at the University of Cretes School of Medicine in Iráklion, published
important papers on the inhibitory action of Red Wine Polyphenols
on human breast cancer cells and human prostate cancer cells.
In collaboration with Joseph Vercauteren, professor of pharmacology
at the Université Victor Segalen in Bordeaux and expert in polyphenols,
Elias Castanas added polyphenols derived from from de-alcoholized
red wine to cultures of breast cancer and prostate cancer cells.
The RWP had an antiproliferative effect on the cancer cell lines
in test tube experiments in the laboratory. During a short stay
in Crete in the lovely September weather we had the opportunity
to ask professor Castanas some questions about his important cancer
Assisted cancer cell suicide
To professor Castanas one of the most intriguing discoveries of
his laboratory tests is the very low concentrations of polyphenols
needed to inhibit cancer cell growth. Traditional chemotherapy
is based on a group of cell poisons the success of which depend
on whether the poisons kill the cancer cells before they kill
the patient. Polyphenols are non toxic compounds; as a matter
of fact it looks as if the RWP have very few side effects. So
if the polyphenols do not poison the cancer cells, how do they
manage to inhibit and eventually kill them? Castanas has an idea
that includes the phenomenon of apoptosis: programmed cell death.
The general purpose of apoptosis is to have any cell that suffers
from irreparable DNA damage kill itself. Maybe the action of RWP
on cancer cells can be described as "assisted suicide". Elias
Castanas and his colleagues are working hard to find the answers.
His laboratory is doing some preliminary animal (mice) studies
that seems to back his test tube research on cancer cells. No
studies with cancer patients has yet been performed as far as
Castanas knows, and besides he warns that such studies are premature.
"Science is five years away from proving whether wines antioxidant
polyphenols do kill breast and prostate cancer cells in humans".
Other polyphenols to look for
In his tests professor Castanas has used several different polyphenols
such as quercetin against cancer cell lines. However, an extract
of total RWP is what he favours for his experiments. So far more
than 200 polyphenols have been identified in red wine, and Castanas
has the opinion that the combined group of polyphenols is more
active than the single compounds by themselves.
Professor Castanas has conducted some experiments with tea polyphenols
and the results were more or less the same as for RWP. He has
not yet had the opportunity to work with beer polyphenols, however,
Castanas is familiar with some of the polyphenols in beer. In
his opinion there is no substantial mechanistic difference between
the polyphenols in wine, beer and tea, however, based on his experience
RWP millimol per millimol have a higher antioxidant capacity than
Bioavailability of polyphenols
The question of bioavailability is a crucial question: if you
drink a bottle of full-bodied red wine you consume about 2 grams
of RWP; what part of these healthy compounds is absorbed during
the process of digestion to become available to target tissues
like the endothelial cells of blood vessels or the nerve tissue
of the brain? Professor Castanas has good news to wine drinkers:
alcohol protects the RWP, so a glass of Cabernet Sauvignon is
a good vehicle for polyphenols. For those who want a steak on
the plate to go with their Cabernet here is more good news: proteins
have a dual action protecting the RWP from oxidation and increasing
the bioavailability of the healthy compounds. That added bonus
leads directly to Elias Castanas favourite advice concerning
a sufficient daily intake of polyphenols: eat a normal meal with
a variety of foods like fruit, vegetables, legumes, olive oil,
bread and fish accompanied by moderate consumption of wine.
Polyphenols on the table or in a capsule?
Who wants to spend hours in the kitchen scraping carrots, cleaning
fish and peeling fruit? Why not relax in the sun with an exciting
book washing down a capsule of RWP with Dry Martini? No, says
the Cretan professor, the antioxidant activity of extracts of
polyphenols is poor compared to the antioxidant power of polyphenols
from natural fruits and vegetables. Besides there is always the
problem of protecting the extracted polyphenols from oxidation.
With an ample supply of antioxidants from various sources like
fruit, vegetables, vegetable oils and wine you arm the cells of
your body with heavy antioxidant artillery to face any oxidant
Professor Castanas is a founder member of the Greek academy of
taste. As a bon vivant with an intimate knowledge of the best
restaurants on the island of Crete the choice between a RWP-capsule
and the fine cuisine of Crete is easy. Raising a glass of fragrant
Mirambelo, a red wine from the grape varieties Kotsifali and Mandilaria
picked from the mountain vineyards of Peza, Castanas toasts the
conclusion from the landmark article on wine and health by St.
Leger and A. Cochrane (Lancet 1979;i:1017-21): "If wine is ever
found to contain a constituent protective agent against I.H.D.
then we consider it almost a sacrilege that this consituent should
be isolated. The medicine is already in a highly palatable form".
Dr. Erik Skovenborg is a founder member of the Scandanavian Medical
Alcohol Board, a specialist in alcohol and health and a member
of the AIM Editorial Board.