Should You Drink Alcohol for Your Heart?
A recent, widely publicized study in the New England Journal of Medicine has led a lot of drinkers to congratulate themselves, and a lot of nondrinkers to wonder if they should start. "Drinking is good for your heart," the newspaper headlines announced, "and the more you drink, the better."
This was a well-designed study funded by the National Institutes of Health. It tracked the drinking habits of 38,000 men—all healthy at the beginning of the study—over 12 years. Men who drank at least three or four days a week had fewer heart attacks than those who drank less. It didn’t matter what they drank—beer, wine, or spirits—or whether they drank it with meals. The positive news didn’t end there. From the point of view of preventing heart attacks, drinking every day was better than drinking occasionally, and three drinks were better than one. Should you say hooray and head for the liquor store?
We don’t think so. Whether, when, and how much you should drink is a complex question, and the answer should be based on your current state of health, medical history, family history, age, sex, and other factors. If ever there was a double-edged sword, it’s alcohol. It benefits people (and society) in some ways and devastates them in others. It is associated with some 100,000 deaths a year from disease and injury—more than the number of deaths from heart disease (estimated at perhaps 80,000) that it may prevent. And alcohol-related deaths occur mostly among the young.
Before you embrace alcohol as heart medicine, here are some Q & A’s to consider.
Does alcohol protect the heart? If so, how?
Dozens of studies have found that moderate or light drinkers have a lower risk of heart disease—30 to 50% lower—than nondrinkers. There is hardly any argument about this now. Furthermore, researchers have found that even when moderate drinkers do have a heart attack, they have a lower risk of dying than teetotalers or heavy drinkers, and older people who drink moderately have a lower risk of heart failure.
Alcohol raises blood levels of HDL ("good") cholesterol—which removes cholesterol from the bloodstream—and thus helps prevent hardening of the arteries (atherosclerosis). Alcohol also reduces the stickiness of platelets in the blood and thus helps prevent the blood clots that cause heart attacks. Consequently, some people compare alcohol to aspirin as a way to prevent clot formation or break up clots. And, yes, both can be helpful, if taken in small doses. But unlike aspirin, alcohol is intoxicating and potentially addictive. The point is that alcohol is only one of several things that may protect your heart. You can reduce your risk of heart disease without drinking at all.
How clear is the evidence about the protective effect?
The evidence so far is very clear. Yet there has never been a large-scale, long-term, well-designed clinical trial testing the effect of alcohol. No matter how carefully conducted, nearly all the studies, including the one mentioned in the first paragraph, have been observational. That is, they followed groups of drinkers and nondrinkers and compared their health over time—a valuable kind of research, but never definitive. Remember, when the evidence about hormone replacement therapy (HRT) and its benefits for women’s hearts—evidence gleaned from observational studies—was tested in controlled clinical trials, the benefits vanished. Indeed, HRT turned out to do some harm.
It is hard to separate alcohol from all the other factors that affect heart disease risk (that is, "control" for those factors) in a study. For instance, moderate drinkers may have healthier habits to begin with—and thus be less likely to have heart disease. Similarly, women taking HRT tended to lead healthier lives and be better educated and more well-to-do, which may have accounted for their lower risk.
What other health benefits, if any, does alcohol have?
Even as little as one drink a week may protect against ischemic stroke (the most common type). Some research also suggests that moderate drinking may cut the risk of developing dementia, including Alzheimer’s disease.
Is wine a better choice than beer or spirits?
It’s almost certainly the alcohol that’s protective, so it doesn’t matter much which beverage you drink. Nevertheless, how you drink the beverage may be important. Beer and wine tend to accompany food—and food slows the absorption of alcohol, which is good. Furthermore, people who drink at meals, especially in the company of others, tend to keep intake moderate. Heavy drinkers usually drink outside of meals. It’s true that wine (red or white) contains certain phytochemicals that may protect against heart disease or even cancer—and nonfermented grape juice also contains these compounds. Beer and spirits, made from grains and other plants, have phytochemicals of their own. Wine may simply seem healthier than other drinks because wine drinkers tend to be better educated and more prosperous than other drinkers, which means they tend to have better diets and better health care.
Isn’t it wine that protects the French from heart disease—even though they eat so much cheese, meat, and butter?
Wine is only a small part of the picture. This is the famous "French paradox"—the French diet generally includes relatively high amounts of animal fat, but the French have lower rates of heart disease than Americans. Most important, though, the French tend to consume fewer calories and to be more active. And while the French have a lower death rate from heart disease, French life expectancy is only a year longer than that of Americans. In any case, wine consumption has been falling in France for decades, and half of all adults don’t drink at all. It would be unwise to conclude from all this that drinking wine will make up for a diet high in calories and saturated fat.
What is "moderation"?
This is a tricky question, and it varies according to your age and sex. The official definition of a "drink" is 12 ounces of beer, 4 to 5 ounces of wine, and 1.5 ounces of 80-proof spirits. Most people are surprised to learn that these all contain the same amount of pure alcohol, about half an ounce (a little more in the spirits). Moderate intake is no more than one drink per day for a woman, on average, or two drinks for a man. Most studies have found that people who drink this much have the lowest overall mortality rate—lower than nondrinkers, occasional drinkers, and heavy drinkers.
But, in fact, the studies diverge. The new one described in the first paragraph found higher intakes beneficial. Other studies have found lower intakes to be best. Moreover, if it’s healthy for a man to have up to 14 drinks a week, can he drink six on Friday and six on Saturday and abstain the rest of the week? Probably not—binge drinking appears to be harmful. What about body size: is it okay for a tall man who weighs 200 pounds to drink more? What about an athletic woman that same size? Or a man 5'4" and thin? Even one drink can be too much for a very small woman. Obviously, size can sometimes trump gender, or at least confuse the issue. And age comes into play, too, since alcohol affects older people more (see below).
Another problem: Portion inflation occurs not only on your plate, but in your glass. Many bars and restaurants do not serve standard-sized drinks, and what’s served as one drink actually may be the equivalent of two or even three. Most people are pleased to be served generously—but you can’t take half your drink home in a doggy bag, as you can your entree. If you ordinarily serve wine or spirits at home without measuring, it might be instructive to measure and see how close you come to the standard serving sizes. That will give you some idea, too, of how much you’re getting in a restaurant.
Why are the guidelines different for men and women?
Alcohol affects men and women differently. A woman will get more intoxicated than a man from the same amount of alcohol. Women tend to be smaller, with a lower percentage of water and a higher percentage of body fat. Since alcohol is distributed through body water and is more soluble in water than in fat, blood alcohol concentrations (BACs) in women tend to be higher. In addition, the stomach enzyme that breaks down alcohol before it reaches the bloodstream is less active in women. Alcohol also carries additional health risks for women, since heavy drinking boosts the risk of osteoporosis. Women are more prone to suffer liver damage from heavy drinking, too.
Is "moderation" the same for older people?
The definition of moderate changes as you get older. Most experts think that after 65, moderation means half a drink a day for a woman, one drink for a man. If you’re over 65, you probably can’t hold your alcohol as well as you used to. That’s because your body doesn’t process alcohol as well, so you end up with a higher BAC than a younger person would. And you feel the effects more from a given BAC. Alcohol is doubly risky for hip fractures, too: not only does excessive drinking decrease bone density, it also increases the risk of falls in older people. Alcohol can interfere with many medications older people take, as well as increase age-related driving risks.
What about breast cancer?
The American Cancer Society lists alcohol as a risk factor for breast cancer, but most of the evidence concerns heavy drinking. Studies have yielded conflicting results about light to moderate drinking. Should a woman have a drink a day to ward off heart disease and forget about the possible breast cancer risk? Nobody should start drinking to protect the heart. But if you already have a drink a day, there’s no health reason to quit, unless you know you are at high risk for breast cancer. Even then, the evidence is far from clear.
Why does the American Cancer Society recommend
restricting alcohol or abstaining?
Because even a moderate intake may increase the risk of cancers of the mouth, esophagus, liver, bladder, pancreas, and colon—besides the concern about breast cancer.
Wouldn’t it be okay for a pregnant or nursing woman to drink just a small amount?
If you are pregnant, trying to conceive, or nursing, you should abstain. Alcohol harms the fetus and the nursing infant, and is a leading cause of birth defects and mental retardation. No one has been able to determine if any level of intake—even one drink now and then—is safe.
Who, besides pregnant women, should steer clear of alcohol?
• Anyone who is unable to drink moderately. This includes recovering alcoholics and possibly those with a strong family history of alcoholism.
• Anyone taking sedatives, sleeping pills, antidepressants, or anticonvulsants should get medical advice about whether these drugs can be safely combined with alcohol. Alcohol can interact with many other medications, too, including over-the-counter pain relievers. When you get a new prescription, ask whether it’s okay to drink. With nonprescription medication, read the label carefully and abstain if necessary.
• Don’t drink if you are planning to drive or operate machinery within the next few hours. If you have had a drink, don’t get behind the wheel.
• Don’t drink if you have uncontrolled hypertension, high blood levels of triglycerides, abnormal heart rhythms, peptic ulcers, or sleep apnea. If diagnosed with any disorder, talk to your doctor about the advisability of drinking.
What are other risks of heavy drinking?
Heavy drinking increases the risk of liver disease, damage to the brain and pancreas, and hemorrhagic stroke. It can damage heart muscle. It increases the risk of falls, injuries, car crashes (often involving pedestrians who have been drinking), workplace injuries, firearms injuries, homicides, and suicides. It contributes to domestic violence and child abuse.
Should anybody start drinking for heart benefits?
Few doctors think so, particularly since much is left to learn and alcohol is so risky. If you don’t drink, for whatever reason, don’t feel pressured to start. There are better ways to prevent heart disease: following a heart-healthy diet, exercising regularly and vigorously, not smoking, keeping your blood pressure under control, and losing weight if need be. On medical advice, you may also want to take low-dose aspirin and, if necessary, a cholesterol-lowering drug. If you already drink moderately, you are probably getting some additional benefit. But do consider your age, sex, and family history. Remember that "moderation" for a woman means no more than one drink a day, on average, two drinks for a man. And that if you are past 65, you should probably cut that amount in half.
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