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When physicians talk about alcohol, it is generally in relation
to alcohol abuse - a problem throughout the world that no one
takes lightly. Some physicians have been reluctant to consider
the new data pointing out many health benefits from moderate drinking.
Similarly, public health officials and government regulatory agencies
that have always focused on alcohol abuse find it difficult to
incorporate emerging data on moderate drinking into their messages.
This paper provides a brief overview on the relation of moderate
alcohol consumption to health and disease, and illustrates the
reluctance of some to accept new information or even attempts
to spread misinformation about alcohol and health.
Early Studies on Alcohol and Health and "Political Correctness" In 1974, after the Framingham Heart Study, being supported by
the National Institutes of Health (NIH), had been in operation
for more than 25 years, a report on the factors related to deaths
from CHD was prepared. It contained strong evidence that individuals
who smoked cigarettes, had high levels of blood cholesterol, and/or
had high blood pressure were much more likely to die from heart
disease.In the same paper there were also data showing a strong
reduction in the risk of death from CHD associated with moderate drinking.
When the senior staff at NIH saw the information that moderate alcohol apparently reduced the risk of mortality from heart disease, they demanded that the authors in Framingham remove this information from the publication. Dr. Carl Seltzer, the scientist in Framingham who had analysed the alcohol data, revealed in 1997 that NIH officials notified him to not include the information on alcohol stating: "An article which openly invites the encouragement of undertaking drinking with the implication of prevention of CHD would be scientifically misleading and socially undesirable in view of the major health problem of alcoholism that already exists in the country." Further, they urged an article maintaining the "conclusion of no significant relationship of alcohol intake to the incidence of coronary heart disease" (which the data did not show). Many other scientists, however, began to publish information starting in the 1970s, with reports coming from studies around the world. The number of publications on moderate drinking increased markedly after the 60 Minutes program on the "French Paradox" in 1991. Of hundreds of studies
published in the scientific literature on alcohol and heart disease
over the past decade, the results have been amazingly similar:
almost uniformly, they have demonstrated that moderate drinkers
have much less coronary heart disease.
Mechanisms by Which Alcohol Reduces the Risk of Cardiovascular
Diseases It is now clear that the rates of most types of cardiovascular
disease(CHD, ischemic stroke, peripheral vascular disease, and
congestive heart failure) are lower in moderate drinkers than
in non-drinkers. Scientists have identified many mechanisms by
which alcoholic beverages reduce the risk of CHD. The most-studied
effect is on the levels of blood cholesterol. Any type of alcoholic
beverage lowers the LDL-cholesterol (the "bad cholesterol") slightly;
but even more importantly, markedly increases the levels of HDL-cholesterol, the "good cholesterol."
Moderate drinkers are also less likely to form clots within the arteries to the heart (leading to a myocardial infarction), to the brain
(leading to stroke), and to other organs. Part of the protection
against blood clots relates to the effects of alcohol on decreasing
the "stickiness" of blood platelets (a function similar to aspirin);
platelets tend to aggregate and lead to clots within arteries.
The decrease in clotting is related both to alcohol and to non-alcoholic
substances present in certain beverages, especially red wine and
dark beers. Many of the effects on clotting are transient effects,
and the beneficial effects may last only for 24-36 hours after
someone has consumed alcohol. Much of the protection against heart
disease of the French may relate to drinking with meals every
day. Drinking only on the weekend, especially "binge drinking,"
is an unhealthy way to drink.
The scientific literature is increasingly demonstrating that alcohol
has numerous other effects that relate to the development of atherosclerosis
or heart disease. Some of these effects are due to antioxidants, particularly high in red wine, that decrease the oxidation of the harmful LDL-cholesterol; oxidation makes LDL more likely to be incorporated into the vessel wall and lead to atherosclerosis. Further, alcohol and many of the polyphenols that are also present in red wine and certain other beverages are now known to have favourable effects directly on the lining of blood vessels, the vascular endothelium, which is intimately involved in the development of atherosclerosis and heart disease.
While heavy drinkers tend to be more likely to develop hypertension (high blood pressure), itself an important risk factor for coronary disease, it is now known that light-to-moderate drinkers have no increase in the risk of hypertension. Further, the occurrence of stroke and CHD, the two major sequelae of hypertension, is lower among moderate drinkers. Other potentially important effects of alcoholic beverages are improvements in glucose metabolism: moderate drinkers are less likely to develop diabetes, and diabetics
who drink moderately are less likely to have a heart attack. Another
factor in the protection from alcohol and wine relates to their inhibition of inflammation, which is now realised to be an important factor in the development
of atherosclerosis.
Beneficial Effects of Moderate Drinking on Non-vascular Diseases
Another common disease associated with ageing is osteoporosis.In many studies, moderate drinking increases bone mineral density,
and reduces the risk of osteoporosis and hip fracture. Other diseases
shown to occur less frequently in moderate drinkers than in abstainers
include gall bladder disease and kidney stones. But the most exciting recent scientific findings are that moderate
drinkers have lower rates than abstainers of Alzheimers Disease and dementia. Studies in the Framingham Study, and from France, Holland and Australia, and elsewhere, show that moderate drinkers tend to have better memory and cognitive functioning, and are less likely to develop dementia. The mechanisms for such protection may relate to prevention of atherosclerosis in the blood vessels supplying the brain. In addition, recent reports have emphasized that moderate alcohol consumption reduces the risk of infection with many types of bacteria or viruses. The most recent paper
showed that food poisoning from salmonella was considerably lower
among guests who consumed alcohol.
Adverse Health Effects of Drinking There are many adverse health effects from drinking too much,
or drinking inappropriately (as just before driving). Heavy drinking
can lead to cardiac problems such as heart muscle disease (cardiomyopathy) or sudden problems
with the heart beat (arrhythmias) that can lead to sudden death.There
are a large number of serious neurological diseases that may occur among alcoholics, plus a number of other diseases
referred to as "alcohol-related diseases," that include cancer of the mouth, throat, and esophagus and cirrhosis
of the liver; these are not diseases of moderate drinkers. The
only important chronic disease that may relate to moderate drinking is breast cancer. Many studies have shown that the risk
of breast cancer is increased by alcohol consumption, with an
estimated increase in risk of about 10% for women averaging one
drink per day. But the data are not consistent, in our review
of 5,000 women in the Framingham Study, followed for 25-50 years
(which is until death for almost one half of them), we found no
increase at all in breast cancer risk for women who consumed alcohol.
Even if there were a 10% increased risk of breast cancer for consuming
one drink per day, one must realise that the same amount of alcohol
has a much greater effect on reducing the risk of more common
causes of death: CHD and stroke. Thus, post-menopausal women who
drink moderately have, on average, a net health benefit from their moderate consumption. Further, recent data from the Nurses Health Study and other studies suggest that women who are consuming adequate folate in the diet have no increased risk of breast cancer from moderate drinking.
Alcohol and Total Mortality
The bottom line is total mortality. What are the net effects on total mortality of alcohol? It depends on how much you drink: alcoholics do not live as long as abstainers, but moderate drinkers live longer than abstainers. In a study of almost 1 million Americans by the American Cancer Society, the risk of dying of any cause was related to the reported intake of alcohol of the participants. For both men and women, the risk was 21% lower for moderate drinkers than for abstainers. Data from the Copenhagen Heart Study and essentially every other prospective study in the last two decades showed similar results. Deaths in the Copenhagen Study had similar results attributable to excessive alcohol consumption were considerably fewer than deaths attributed to not drinking, with the excessive deaths in the abstainers primarily from their increased risk of heart disease and stroke.
Alcohol as Part of a "Healthy Lifestyle" The definition of a "healthy
lifestyle" generally includes not smoking, not being obese, exercising
regularly, and eating a balanced diet. We now have good scientific
data suggesting that we can add alcohol to that definition. Two
recent publications from the Nurses Study defined a "healthy
lifestyle" that, in their data, was associated with 75% fewer heart attacks and more than 90%
fewer cases of diabetes! It is also probable that this lifestyle would reduce the risk
of most cancers, and would surely lead to greater longevity of
life. This healthy lifestyle is defined in the table below:
Definition of a "Healthy Lifestyle"
(1) Avoid obesity (BMI < 25)
(2) Consume a healthy diet (high in fiber and unsaturated fat and low in trans fat and glycemic load)
(3) Engage in moderate to vigorous physical activity (for at least half an hour per day);
(4) Avoid smoking
(5) Consume at least one half of a typical drink of an alcoholic beverage per day. (based on Stampfer, et al, New Eng J Med 2000; Hu, et al, New Eng J Med 2001)
Since these initial studies have been published, a large number of prospective studies have shown that following these guidelines, often included with what is generally considered as a ”Mediterranean-type diet,” is associated with less cardiovascular disease and improved total mortality. One key component of all of these lifestyles is the regular consumption of a small amount of alcohol.
Should Everyone Drink Alcohol?
Despite the strong scientific data showing that moderate drinkers have much less heart disease and stroke, and that they live longer, no one is suggesting that everyone should drink alcoholic beverages. There are some who find any drinking to be against their religious or ethical beliefs; and there are some people who have certain medical conditions that make it inadvisable for them to drink. On the other hand, people who are at risk of CVD (most middle-aged men and most post-menopausal women) should be informed that moderate drinking is one lifestyle habit that may reduce the risk. The UK Department of Health in its "Report on Sensible Drinking" released in 1995, stated the following: "While some people do not wish to take up drinking, for religious or other reasons, or there may be medical grounds for them not to do so (and such individuals should make other lifestyle changes to improve health and lower the risk of coronary heart disease), middle aged or elderly men and post menopausal women who drink infrequently (less than one unit per day) or not at all may wish to consider the possibility that light drinking might benefit their health."
Challenges to the Message of Health Benefits of Moderate and Responsible Drinking There continue to be challenges to the scientific data on the health benefits of moderate drinking. Many of us are frequently called upon by journalists, other scientists, and the industry to comment on certain new studies on alcohol and health. Further, there continue to be mis-guided statements that exaggerate the dangers of moderate drinking and question its health benefits: Example : An "American Heart Association Advisory on Wine & Health" was published by Goldberg et al in Circulation, 2001. The advisory
suggested that wine and alcohol consumption has little scientific
basis for lowering heart disease risk, has many potential dangers,
and that alcohol should not be advised for the prevention of heart
disease. Further, it stated that hypertensive people should avoid
alcohol, and suggested that alcohol is not very effective in raising
HDL cholesterol.
In the response from our Institute (published in Circulation,
2001), we pointed out that the advisory fails to mention numerous
experiments showing that alcohol raises HDL quite markedly. Further,
we stated that recent studies (ignored in the advisory) showed
that moderate drinking decreases the risk of complications and
death from congestive heart failure.We argued that the statement
in the advisory that "Patients who are hypertensive should avoid
alcoholic beverages," is not based on scientific data and could
be dangerous -hypertensive patients are at greatly increased risk
of heart disease and stroke, two diseases that would be much more
likely if such patients avoided alcohol completely. We concluded
our response: "In a culture where cardiovascular disease is the
leading cause of death, telling people to avoid any alcohol consumption
because of potential dangers or unproven theories is not in
the best health interests of the public. Let us not be afraid
to just tell the truth."
Conclusions It is important that physicians, government officials,
and the public have scientifically sound information upon which
to base decisions regarding alcohol and health. Some of the reluctance
of those who deal with abuse to present a balanced picture may
relate to their fears of presenting a "mixed message." They prefer
to emphasize the adverse effects of abuse and to have a simple
"Just say no" message for all alcohol consumption. Unfortunately
(or rather, fortunately!), a yes/no message does not work for
alcohol in general. As with most things in life, excesses in habits,
foods, or alcohol may have problems that are not inherent in the
activities or substances themselves, but in their inappropriate
use. Abraham Lincoln, the 16th president of the US, stated "It
has long been recognised that the problems with alcohol relate
not to the use of a bad thing, but to the abuse of a good thing."
There can never be a general recommendation for everybody to drink.
On the other hand, I believe that it is unethical to withhold
from the public sound advice on drinking and health. Accurate
and balanced information needs to be presented to all - the message
from scientists is now very clear: for most individuals in Western
societies, moderate drinking can be an important component of
a "healthy lifestyle."
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