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One of the most popular episodes shown on 60 Minutes
was entitled "The French Paradox" (November 17, 1991), which reported that the
consumption of wine by the French protected them against the heart
disease-producing effects of their high-fat diet. The popularity of this
message is of no surprise: People love to hear good news about their bad
habits.
The French have 3 times less heart disease in each age
category than Americans. The reasons given for this difference were: The
French do not eat between meals; they take more time to eat their meals, as
opposed to our habit of rapid gorging of fast foods; and they do not eat the
amount of processed foods that Americans consume. Also, the French eat more of
their dairy products as cheese than as milk.
One researcher, who based his ideas on rat
experiments, speculated that cheese did not cause as much artery damage as milk
does. Nevertheless, there is no scientific basis for such a suggestion, and the
literature -- such as a 1992 study in The Lancet has reputed it. Other
investigators have suggested that the French love for garlic may be a life
saver.
The question is this: Is there really a
paradox?
The apparent difference between French and,
say, American heart disease rates may be an artifact of the traditional French
diet, which currently is changing, unfortunately. During the past 25 years, the
French diet has become much higher in fat and lower in alcohol than in the past.
Data from the United Nations Food and Agriculture Organization (FAO) has found a
40 percent increase fat consumption by the French during the past 25 years. The
proportion of fat consumed in France increased 29 percent from 1961 to 1963,
and 39 percent from 1986 to 1988. Heart disease takes decades to develop;
thus, the heart disease rates may not have had time to catch up.
Fat consumption for Americans reached 39
percent of their total calories in the 1950s, and has remained at or above that
level ever since. Since the French intake in fat and alcohol is now approaching
that of the Americans, there is every reason to believe that with sufficient
time they will suffer the same death rate from heart disease as we do. As of
now, they have only had 4 to 6 years of high-fat eating compared to more than 50
plus years for Americans.
Pros and Cons of Alcohol Consumption
The research on alcohol may, on the surface,
present a contradictory picture. There are some benefits to moderate alcohol
consumption, but on the whole they are small in comparison to the dangers of
excessive intake of alcohol.
Since stories of the "French paradox"
began to surface, the scientific literature has reported a number of articles on
the relationship between heart disease and alcohol, particularly red wine. This
benefit is not new news. During my days in medical school I saw, firsthand, in
autopsies, that skid-row alcoholics often had the cleanest arteries. Their diet
was, of course, mostly "liquid vegetarian" in the form of alcoholic beverages,
often wine. They were, however, not known for their longevity -- just their
clean arteries.
The research clearly shows that moderate
consumption of alcohol -- defined as about an ounce (20 to 30 grams) of alcohol
a day, or 2 to 4 drinks a day -- is associated with a 40 percent reduction in
the incidence of heart disease. Beer, wine, and spirits seem to be equally
protective. One of the reasons moderate alcohol consumption is associated with
a reduction in the incidence of heart disease is that it raises HDL- cholesterol
levels. HDL, you will recall, helps reduce the likelihood of heart disease by
removing cholesterol from arteries and tissues, and out of the body through the
feces. However, the HDL-raising effects of alcohol are not a straightforward
equation, meaning that higher amounts of alcohol do not give you more HDL in
your blood.
HDL cholesterol can be divided into smaller
parts, or sub fractions. Subfraction HDL2 changes very little with
alcohol intake, whereas HDL3 rises substantially when alcohol is
consumed. The early research suggested that only HDL2 levels were
associated with changes in a person's risk of heart disease. However, more
recent research has shown that both subfractions are associated with lower heart
disease rates. Also, the more recent studies report that both types of HDL rise
with alcohol consumption. However, elevation of HDL cholesterol appears to
account for only half of the protective effect of alcohol. There's more to it
than just HDL.
Alcoholic beverages, especially red wine,
contain powerful antioxidants. These substances prevent LDL particles from
being oxidized and thus forming atherosclerotic plaque in the arteries.
Antioxidants, including quercetin, epicatechin, and resveratrol, are found in
the non alcoholic components of wine. Red wine diluted 1000-fold with water has
been shown to inhibit LDL oxidation significantly more than vitamin E (a-tocopherol).
In addition, wine seems to thin the blood,
thus preventing clots from forming. A heart attack occurs as a consequence of
two unhealthy conditions: the rupture of volatile atherosclerotic plaques and
the creation of large artery-blocking clots that form on top of the ruptured
plaque (a process called thrombosis). While animal fats promote the rupture of
plaques and the formation of large clots, alcohol decreases the clotting
activity of the blood, and thus reduces the chance of a heart attack. This
occurs because alcohol inhibits the tendency of platelets to aggregate to form
blood clots. A study of 1600 people showed small amounts of alcohol reduced
the tendency of their platelets to aggregate. This effect of thinning of the
blood can also increase bleeding tendencies and may account for the increased
risk of hemorrhages in heavy alcohol users.
Adverse Effects on the Heart
Heavy alcohol consumption over time can
damage the liver so severely that it can no longer synthesize HDL cholesterol,
dramatically increasing the risk of atherosclerosis. Excessive alcohol
consumption is the second most common cause of elevated triglycerides (diabetes
is the first). Moderate alcohol intake shows no consistent effects on
triglyceride increases, however. Elevated triglycerides are associated with an
increased risk of heart attacks, diabetes, and high blood pressure. They can
become sufficiently elevated to cause inflammation of the pancreas.
Another cardiovascular disease associated
with alcohol consumption is heart failure. Heart decomposition typically occurs
in men between the age of 30 to 55 years who have ingested at least 3 ounces (80
g) of alcohol daily for a minimum of 10 years. Chronic excessive alcohol
consumption is a major cause of cardiomyopathy--a severe form of heart muscle
failure. There is also an increased incidence of sudden death that peeks at
about the age of 50 in alcoholics. Bouts of heavy drinking have caused the
onset of irregular heart rhythms. The most common arrhythmia associated with
alcohol is atrial fibrillation.
Heavy drinking was twice as common in men and
seven times as common in women who suffered brain hemorrhages. Acute heavy
alcohol consumption is also characteristic of young adult stroke victims.
People who decrease their alcohol intake soon lower their risk of strokes.
Social drinking is associated with a small
rise in systolic blood pressure (the top number). In heavy drinkers the rise
may be substantial. This increase in blood pressure may be caused by the
effects of alcohol on blood pressure elevating hormones (aldosterone, renin, and
catecholamines) and by an increase in the activity of nerves that cause blood
vessels to constrict, thus increasing the resistance to blood flow within the
arteries.
The benefits for the reduction of heart
disease with the moderate use of alcohol revealed by scientific research have
caused some doctors to advocate temperate drinking. But, the overall effects
on health are negative, especially for people who fall within the 10 percent of
the population who are problem drinkers. Obviously, we are all responsible for
our own behavior and ultimately each of us must decide if we are abusing alcohol
or not. When it comes to matters of public health policy, however, physicians
must take a responsible and sober approach. Our position cannot be one of
advocacy of alcohol, nor should we blur the issues that surround the use of
alcohol, especially since alcohol is often linked to many serious social
problems, such as drunken driving, violence and family abuse. Although
moderate use of alcohol reduces risks of heart disease, it dramatically
increases the risks of dying from other causes, such as cirrhosis, loss of the
liver, cancer, violence, and accidents. For example, people over the age of 35
with a previous arrest for driving while impaired (DUI) have nearly 12 times the
risk of dying in an auto accident compared to controls with no history of a DUI
offense. Obviously, the first indication a person has problems with alcohol
deserves serious attention. Regardless of how mixed the messages may seem,
efforts by everyone in our health care system should be to decrease the use of
alcohol.
Having habits are part of our birthright, but
a part we can change with the right information and a little effort. This
chapter is a step in that direction, I hope. Now, ask yourself, " How do these
substances make me feel?" Then ask yourself, "Wouldn't I be a lot better off
without them?"
References:
Real difference is the French have only recently
changed their diet:
Nestle M. Wine and coronary heart disease. Lancet
340:314, 1992.
Criqui M. Does diet or alcohol explain the French
paradox? Lancet 344:1719, 1994.
Alcohol associated with less death from heart disease:
Lazarus N. Change in alcohol consumption and risk of
death from all cause and from ischemic heart disease. Br Med J 303:553, 1991.
Rimm E. Prospective study of alcohol consumption and
risk of coronary disease in men. Lancet 338:464, 1991.
Alcohol raises HDL cholesterol of both types:
Steinberg D. Alcohol and atherosclerosis. Ann Intern
Med 114:967, 1991.
Wine has other benefits, like acting as an antioxidant
and antithrombotic:
Langer R. Lipoproteins and blood pressure as biological
pathways for effect of moderate alcohol consumption on coronary heart disease.
Circulation 85:910, 1992.
Frankel E. Inhibition of oxidation of human low-density
lipoprotein by phenolic substances in red wine. Lancet 341:454, 1993.
Renaud S. Wine, alcohol, platelets, and the French
paradox for coronary heart disease. Lancet 339:1523, 1992.
Renaud S. Alcohol and platelet aggregation: the
Caerphilly Protective Heart Disease Study. Am J Clin Nutr 55:1012, 1992.
Fuhrman B. Consumption of red wine with meals reduces
the susceptibility of human plasma and low-density lipoprotein to lipid
peroxidation. Am J Clin Nutr 61:549, 1995.
Adverse effects of alcohol:
Steinberg D. Alcohol and atherosclerosis. Ann Intern
Med 114:967, 1991.
Regan T. Alcohol and the cardiovascular system. JAMA
264:377, 1990.
Brewer R. The risk of dying in alcohol-related
automobile crashes among habitual drunk drivers. N Engl J Med 331:513, 1994.
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