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Let us review today the results of mostly recent reports of the
effects upon health of components of wine other than alcohol.
As we have been discussing in these commentaries, moderate consumption
of wine and other beverage alcohol is associated with a longer
and healthier life than that of abstainers, an observation supported
by a great mass of evidence. Much of the benefit, at least 50
percent, appears to be derived from the alcohol itself, which,
when abused, is the only component of wine that adversely affects
health. Alcohol's health benefits chiefly favor the cardiovascular
system, and are dramatically reflected in reduced risks of atherosclerotic
heart attacks, ischemic strokes, and limb amputations due to compromised
blood supply.
There are other components of wine that contribute to the same
benefits, but they are more complex and variable, and less precisely
defined.
Scientific views on these compounds are not unanimous. These are
mostly polyphenolic flavonoids, which can be referred to as antioxidants,
according to their most attractive function. They are, of course,
found in grapes, chiefly the skins, so their concentrations tend
to be higher in red wines (skins participate in fermentation)
than white (skins separated). Their functions in the vine are
only partially known--antifungal, for one. These antioxidants
are much less available in other beverages. Among the best known
and most biologically active are resveratrol, quercetin, and the
catechins.
The antioxidants with which we are concerned are a class of phytochemicals,
that is, compounds of vegetable origin. They are not exclusive
to grapes, although grapes are relatively richly endowed with
them. They are also found in allium vegetables (onion, leek, garlic,
shallot), broccoli, spinach, blueberries, strawberries, tea and
chocolate.
For some time there was doubt about whether antioxidants could
be absorbed when ingested and whether they were biologically potent.
By now the doubts have been resolved in favor of the antioxidants.
They appear to be even more active than the more renowned antioxidant
vitamins A, C, and E.
The average man lived to age 43 early in the twentieth century.
Enormous gains were made, largely resulting from prevention and
treatment of infectious diseases by public health measures, immunizations,
antibiotics, and improved general medical techniques, and from
improved surgical techniques and blood transfusions. We appear
to be approaching a plateau, with the only clearly visible gains
to be made the control of human-engendered carnage, of poverty-related
afflictions, and the elimination of diseases caused by tobacco.
The solutions to other plagues still elude us.
At or near the top of causes of death and disability are diseases
of the heart and blood vessels, cancer, and degenerative disorders.
Free radicals and oxidation figure heavily in the causation and
aggravation of these ills. Free radicals, not a political term,
are high reactive compounds produced normally as the body uses
oxygen. Smoking, radiation, and certain chemicals enhance their
production, thus straining, sometimes overwhelming, the body's
natural enzyme-mediated antioxidant defense system. This is why
there is so much interest in importing additional antioxidants,
those derived from food and drink. Look at a partial list of diseases
suspected of being able to be relieved by antioxidants: heart
attack, stroke, other complications of blood-vessel disease, cancer,
Alzheimer's disease and other dementias and degenerative disorders,
immune dysfunction, cataract, macular degeneration. Aging itself
may be retarded by antioxidants. Precise formulas for each of
us are not yet possible - we have much to learn. Antioxidants
may not always be entirely benign.
Recent studies of the cardiovascular system report reduction of
risk of heart attack in the elderly by a diet high in vitamin
A, but not vitamin C or E, reduction in risk of ischemic stroke
associated with the antioxidants of fruits and vegetables (but
no benefit from vitamins A, C, or E), and improved coronary artery
function apparently due to vitamin C. The antioxidants of wine
and grape juice favorably modulate the blood clotting that climaxes
heart attacks and strokes, and help further by relaxing blood
vessels and inhibiting the oxidation of LDL (the "bad") cholesterol
to its dangerous form. Similar, but less-established benefits
may result from the antioxidant flavonoids found in tea and chocolate,
virtually identical to those of wine.
Second in importance to their cardiovascular benefits are wine's
antioxidants' actions against cancer. Likely we are just beginning
to peel off layers of understanding. By both antibacterial effects
and by scavanging destructive superoxide to reduce tissue injury,
these compounds may prevent cancers of the stomach and other organs.
Quercetin has been noted to inhibit the growth of cancer and leukemia
cells, and to potentiate anticancer chemotherapy. One report has
resveratrol initiating a process one might term cancer-cell suicide,
but another suggests that antioxidant vitamins may do the opposite,
resulting in larger brain tumors in mice. (No harm comes to cancer-free
mice of this strain). Diligent science is hard.
The rest of the demonstrated or suspected benefits of the antioxidants
that are found in wine are in earlier days yet than those already
cited.
Improved brain and muscle function has been found associated with
moderate wine consumption and with supplementation with blueberries,
strawberries, and spinach. Among a number of studies indicating
that moderate wine consumption correlates with preservation of
mental capacity, that comparing aging twins is particularly impressive.
The co-twin of each pair who averaged one to two drinks per day
scored higher intellectually than their counterparts who drank
significantly more or significantly less.
A number of very nasty bacteria and viruses are inactivated by
wine and by grapes (but, surprisingly, in some cases not by alcohol).
One report suggests that antioxidants may help prevent toxemia
of pregnancy.
Finally, a most important subject, weight control. Long noted
but unexplained has been a disparity between the number of alcohol
calories ingested and weight. A peek behind the mystery may be
offered by the recent observation that catechin polyphenols (flavonoid
antioxidants, as found in wine, green tea, etc.) stimulate the
"burning" of body fat.
An ascetical might be inclined to ask why not eat just the fruits
and veggies, and shun alcohol. Fear not, there are reasons enough.
Alcohol in moderation contributes at least half of wine's cardiovascular
benefits, and likely provides numerous other health benefits,
but little, if any, risk. It may enhance the desired actions of
the antioxidants, and, when combined with antioxidants in the
enriching form of wine, its package can't be beat.
* Dr. Finkel, an award-winning wine writer, clinical professor
of medicine at Boston University Medical Center, and chairman
of the Committee on Health of the Society of Wine Educators, comments
regularly in The Wine News on the interrelationships of wine and
health.
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