Health Risks and Benefits of Drinking Alcohol

Every month, it seems, another study shows that “moderate” amounts of alcohol help protect against heart attacks. Yet the studies often disagree about what type of beverage is beneficial, what the optimal intake is, and who will benefit. The U.S. government, in its official dietary guidelines, as well as the American Heart Association, have confirmed the coronary benefits of “moderate” drinking. Yet the American Cancer Society, in its guidelines, has recommended limiting alcohol consumption or abstaining from it, since even a moderate intake may increase the risk of cancer in some people.

It is clear that while heart disease is the nation’s leading cause of death, alcohol’s benefits can certainly be offset by its hazards:

• Alcohol is associated with about 100,000 deaths from diseases and injuries in the United States each year.
• Alcohol may prevent 80,000 deaths from coronary artery disease (CAD) each year, according to one report from the American Heart Association. But that’s merely the mean point of a wide range of estimates (anywhere from 12,000 to 136,000) based on data from a dozen studies.

In fact, both these figures are only rough estimates. It’s hard to say exactly how many Americans die as a result of alcohol consumption. It’s even harder to figure out how many deaths from heart disease may be prevented by moderate drinking. Moreover, such a weighing of the beneficial and adverse effects of alcohol doesn’t take into consideration the big differences between the two groups involved. While most alcohol related deaths occur in relatively young people, the deaths prevented by alcohol are generally in older age groups those with high rates of cardiovascular disease.

So what is the real bottom line on alcohol? Should you start drinking or cut down or even quit?

Which beverages are protective?

Studies have consistently found that a regular consumption of moderate amounts of alcohol helps prevent heart attacks in middle-aged or older men and women by 30 to 50 percent. Red wine has gotten the most publicity, but some studies have found that white wine also helps, and other studies have found that wine, beer, and liquor are all equally effective. Though wine and other beverages contain various antioxidant phytochemicals that may help protect against heart disease and cancer, the crucial element is the alcohol itself.

Scientists estimate that about half of the protective effect comes from alcohol’s ability to boost HDL cholesterol, the “good” kind that removes plaque from the arterial wall. Thus alcohol may reduce atherosclerosis, the hardening and narrowing of the arteries leading to the heart, which can cause a blockage and heart attack. Alcohol also reduces the stickiness of the blood and interferes with the formation of clots.

Wine may seem healthier than other drinks because wine drinkers tend to be better educated and more affluent than other drinkers, which may account for other traits (such as a better diet or better health care) that help keep them healthy. Two studies published in 1999 one from England, the other from Denmark—found that wine drinkers have healthier habits (better diets, less likely to smoke) than other drinkers.

Wine also tends to be consumed with meals, which may be preferable. Food slows the absorption of alcohol, prolonging the potentially beneficial effects on the blood (especially important after a fatty meal) and moderating blood alcohol levels. In addition, people who drink only with meals tend to do so in moderation. Those who drink excessively tend to drink mostly outside of meals.

What is “moderate”?

This is the tricky part. Most experts say that moderation means no more than one drink per day for women and two drinks for men. A standard drink is 12 ounces of beer (the most common size of a bottle or can of beer), 4 to 5 ounces of wine (a smallish glass), or 1.5 ounces of 80-proofliquor (the amount in a not-quite-full shot glass); all of these supply about the same amount of pure alcohol. In most studies, people who drink that much have the lowest overall mortality rates, especially from heart disease lower than teetotalers, occasional drinkers, and heavier drinkers.

However, not all studies have agreed with those numbers. A few studies have found that higher intakes can also be beneficial overall. Other studies suggest that “light” drinking (not even one drink a day, but two to six drinks a week) is better than a “moderate” intake.

A study from Harvard University followed 22,000 male physicians for 11 years and found that those who had two to six drinks a week had the lowest overall death rates. The men who aver- aged two drinks or more a day had the highest death rate, because of an increase in deaths from cancer, primarily lung cancer. But this was an unusual study, in that the men (partly because they were doctors) were quite healthy, and relatively few died from heart disease.

Moreover, only 3 percent of them fell into the “two or more drinks a day” category. Because the study lumped together moderate and excessive drinkers in this highest open-ended category, it couldn’t determine the risks faced by men who consumed only two drinks a day, nor could it define where the real danger begins. Also, the results can’t be extended to women.

In general, problems arise with how drinking levels and patterns are categorized in virtually all the studies. For example, the studies rarely measure when and how alcohol is consumed: 10 drinks a week could mean a beer or two with dinner or two five-martini binges, which would have very different effects in the body. And for various reasons, people may not report their alcohol intake accurately.

Men and women

Alcohol affects men and women differently. A woman will get more intoxicated than a man from the same amount. Women tend to be smaller than men and to have proportionately more fatty tissue and less body water than men. Alcohol is distributed through body water and is more soluble in water than in fat, so the blood alcohol concentration from a given intake will be greater for a woman. Moreover, the stomach enzyme that breaks down alcohol before it reaches the bloodstream is less active in women than in men, so that more alcohol enters the bloodstream from the stomach.

Thus, excessive drinking tends to have more serious long-term consequences for women. They are more likely to develop damage to the liver, heart muscle, and brain at lower levels of alcohol intake than men. Alcohol may also put them at increased risk for osteoporosis and possibly breast cancer. Studies also suggest that alcohol has a greater effect on driving skills in women—and at a given blood alcohol concentration, women have a higher risk than men of dying in a crash.

Alcohol and cancer

Several widely publicized studies have suggested that alcohol increases the risk of breast cancer. But other studies have found no increased risk or found it confined to specific groups: those who consumed more than two drinks a day, or only premenopausal women, or only postmenopausal women. One 1993 study did show that when pre- menopausal women drink, they have higher levels of estrogen in their blood, which might explain an increased risk of breast cancer, if there is one. On the other hand, a more recent study suggested that a compound found in wine may counteract the effect of estrogen in the body. In 1999, research from the ongoing large-scale Framingham study found that alcohol does not increase the risk of breast cancer.

This has resulted in confusion for women, who wonder whether to drink moderately to protect against heart disease or to abstain because of alcohol’s potential effect on breast cancer risk. Remember, however, that heart disease kills 10 times as many middle-aged and older women as breast cancer and that questions still remain about the link between alcohol and breast cancer. If you’re a woman who has a drink a day, there’s no health reason to quit, unless you are pregnant or nursing or possibly if you are at high risk for breast cancer or are on hormone replacement therapy.

Alcohol has been linked to several kinds of cancer. The recent Harvard study found an increased risk of lung, esophageal, gastric, pancreatic, urinary tract, and several other cancers. But studies have yielded inconsistent results about precisely which cancers are affected. One thing is certain: smoking and drinking act together to increase the risk of several cancers.

Other risks linked to alcohol

After tobacco, alcohol is the leading overall cause of premature death in this country—and many of these deaths occur in young adults. Long-term, heavy drinking (three or more drinks a day) increases the risk of liver disease, damage to the jt brain and pancreas, high blood pressure, and ^ hemorrhagic stroke. It can also cause heart dis- ease by damaging the heart muscle. Even moderate drinking during pregnancy increases the risk of fetal alcohol syndrome, which can result in mental retardation and birth defects.

People with type 2 diabetes, who are at high risk for heart disease, may lower their risk by consuming a drink a day. But the well-known risks posed by alcohol, such as interactions with drugs, or falls and accidents, may be particularly dangerous (so be sure to discuss this issue with your doctor if you have type 2 diabetes).

Drinking alcohol also increases the risk of accidental injury and death in a number of settings. A seemingly small amount of alcohol can impair judgment, concentration, and reaction time. In many states a blood alcohol level of 0.10 is defined as legal intoxication. (Some states have lowered this level to 0.08.) Although many factors—such as whether alcohol is consumed with food and how fast it is consumed—affect blood alcohol levels, on average a 170-pound man would reach a blood alcohol level of 0.10 by having four or five drinks in an hour, a 137-poundwoman three drinks.

In 1998, nearly 16,000 people died and more than 305,000 were injured in vehicular crashes where police reported alcohol as a factor. This works out to an average of one person injured every two minutes. Thanks to lowered speeding limits, the wider use of seat belts, and the raising of minimum-age drinking laws in all states to 21, the number of fatalities has decreased by 33 per- cent since 1988. Still, 38 percent of total traffic fatalities in 1998 were alcohol-related. The injured people included not only drivers but also pedestrians, motorcyclists, and bicyclists who had been drinking. (More than one-third of the pedestrians 16 years of age or older who were killed by cars had elevated blood alcohol levels.)

In addition to vehicle and cycling accidents, alcohol takes a toll in workplace and firearms injuries, as well as homicides and suicides. Moreover, alcohol abuse alters judgment and creates unhealthy family dynamics, contributing to domestic violence and child abuse.

Should nondrinkers start?

Few if any medical experts advise nondrinkers to start drinking for health reasons. Alcohol probably kills more people than it saves but the beneficial and adverse effects of alcohol occur with different levels of intake and largely in different groups. Most alcohol- related deaths occur in relatively young people, while deaths prevented by alcohol are generally in older age groups those with high rates of cardiovascular disease.