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How much can I drink safely? How little should I drink for health?
It is generally conceded that alcohol itself provides at least
half of the health benefits of moderate consumption of wine, beer
and cider and all of the health risks of excessive drinking. The
antioxidant polyphenolic flavonoids of the drinks supply the rest
of the benefits.
As we have discussed in these commentaries, a growing mountain
of scientific medical evidence supports the conclusion that moderate
drinkers derive a surprising advantage in health and longevity
compared to abstainers. The risks of heart attacks and related
disastrous complications of atherosclerosis appear to be reduced
by more than 25 percent in moderate drinkers. These disorders
are our most frequent causes of death and disability.
Heavy drinkers encounter steeply increasing risks to health and
longevity as they drink more and longer. (I am considering only
the medical effects of drinking, not influences upon performance
and behavior, about which I am not expert and for which precise
measurements are dauntingly difficult and often confounded.
The now widely recognized J-shaped curve graphically illustrates
this relationship between the quantity of alcohol consumed and
its likely effects on health and longevity.
Although most scientists measure drinking in grams of alcohol,
because we do not carry metric scales and calculators around,
I shall write in terms of numbers of drinks. A drink-equivalent
in alcohol is, on average, about 5 ounces of wine, 12 of beer,
or 1.2 of spirit, each containing approximately 14 grams of ethyl
alcohol.
The liver is the organ most sensitive to the insults of alcohol,
in effect the canary of drinking. On average, a healthy man may
drink 14 ounces of wine daily and within medically safe limits.
Both safety and health benefits are enhanced by consumption of
ones allotment with meals and in steady, regular aliquots, rather than in intermittent
gulps and binges. The liver is less likely to be damaged by a
regular drinking pattern, especially if the total intake of alcohol
is kept in bounds. Heart attacks occur most frequently in early
morning hours; the risk-reducing effects of wine at dinner persist
through the morning.
Sex counts. Because the content in the stomach linings of women
of the alcohol-neutralizing enzyme alcohol dehydrogenase is half
that of men, the upper safe limit of daily wine consumption of
women is set by liver mavens at 7 ounces. So, when my wife and
I share a bottle of wine,....
As excess increases, other organs and tissues are damaged, eventually
irreversibly.
As the beneficial effects of moderate drinking become established,
researchers, mindful of the dangers of excessive alcohol, more
intensely studied just how much alcohol is likely to lead to what,
not at all an easy task. The relationships, still somewhat murky,
are beginning to clear, but results appear to vary with the group
and location of the studies. Let us review the most up-to-date
reliable information.
The Physicians Health Study analyzed data on 89,299 male physicians
followed since 1983. The results we now consider were published
in the Journal of the American College of Cardiology in January,
2000, by J. M Gaziano and colleagues at institutions affiliated
with Harvard Medical School, Boston. In this well-studied group,
those who drank from at least one drink weekly through and beyond
two per day experiences, on average, in the order of 25 percent
fewer cardiovascular deaths, heart attacks, strokes, and related
disorders than those who never or rarely drank. No significant
increase in cancer or other harm was detected.
Similar were the results of the large Nurses" Health Study reporting
on women, published by C. S. Fuchs, et al., in The New England
Journal of Medicine in May, 1995. The women derived the same cardiovascular
benefits as do men, but those that averaged 2 1/2 or more drinks
per day appeared to be at somewhat increased risk for breast cancer.
(Keep in mind that many more women die or are disabled by cardiovascular
disease than by cancer. Individual risk assessment must be done
to estimate ones own relative risks.)
Finally, for todays au courant review, let us peruse Ian Whites
review of drinking among 60,224 deaths among men and 74,824 among
women, as published in the October, 1999 issue of the Journal
of Clinical Epidemiology( see page 11 or full review). The studies
reviewed encompassed the United States, the United Kingdom, Finland,
Denmark, Italy, Australia and Japan. White noted that "moderate
consumers of alcohol have lower mortality than either non-drinkers
or heavy drinkers." He went on to determine the level of consumption,
termed the "nadir," at which death rate is lowest, considering
men and women separately, and reports it to be the equivalent
of 3.5 ounces of wine per day for U.S. men, 5.9 for U.K men, and
1.3 for U.S. women, the most reliable results. These figures seem
low in comparison to those of other reports, but the range within
each group is wide. The differences between countries cannot be
explained at this time. There appears to be no change with older
age.
We have again seen that on average the moderate drinker fares
better than either the abstainer or the abuser. Be aware, however,
that wine is not medicine. We should use it prudently to enrich
life, not to medicate it.
References1. Finkel HE: Wine and health. Wine News 10:14-17, 29
(Feb/Mar) 1994.2. Gaziano JM, Gaziano TA, Glynn RJ, et al: Light-to-moderate
alcohol consumption and mortality in the Physicians Health Study
enrollment cohort. J Am Coll Cardiol 35:96-105, 2000.3. Fuchs
CS, Stampfer MJ, Colditz GA, et al: Alcohol consumption and mortality
among women. N Engl J Med 332:1245-1250, 1995.4. Finkel HE: In
Vino Sanitas? Savage, MD: Society of Wine Educators, 1998.5. White
IR: The level of alcohol consumption awhich-all cause mortality
is least. J Clin Epidemiol 52:967=975. |