When risk of death from heart attack is plotted on a graph against alcohol consumption, studies consistently show a U-shaped curve, which suggests that non-drinkers and heavy drinkers have higher rates of heart disease than light to moderate drinkers. The implication is that moderate drinking offers protection from heart disease.
For years, doctors believed that the death rate among people who do not drink at all was artificially high because it included a substantial number of reformed drinkers, irreparably damaged by alcohol. However, more recent studies which separate life-long drinkers from abstainers have shown that abstainers are still at high risk.
Studies have shown that moderate drinkers have higher levels of high-density lipoproteins (脂蛋白) in their blood. This is the "good" cholesterol that protects against heart disease. Alcohol also appears to reduce the risk of heart diseases. Though drinking alcohol in moderation undoubtedly brings some benefits, it is important not to play down the ers of heavy drinking. Alcohol is related to a string of health problems including cirrhosis (硬化) of the liver, cancer of the mouth, high blood pressure and hemorrhage stroke.
Some people believe that wine, in particular, has additional beneficial properties that set it apart from other alcoholic drinks. The French have significantly less heart disease than does any other industrialized nation except Japan. For example, in Toulouse, France, the annual heart disease death rate per 100,000 men is 78--barely a fifth of the number in Glasgow, Scotland. French doctors believe that the low rate of heart disease is a result of the fact that the French consume large quantities of wine.
The relationship between alcohol consumption and the risk of developing cancer has also been studied. Population studies suggest that people who drink moderately are at less risk than those who do not drink at all. Again, wine may be largely responsible for the benefits.
Other research suggests that drinking moderate amounts of alcohol also reduces the risk of catching everyday infections like colds. A recent study showed that drinking two units of alcohol dally can halve susceptibility to infections.
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