Physical
Effects of
Alcohol The effects of alcohol on the human
body depend on the amount of alcohol in the blood (blood-alcohol concentration). This varies with the
rate of consumption and with the rate at which the drinker's physical system absorbs and metabolizes alcohol. The higher the alcohol content of the beverage, the more alcohol will enter the bloodstream. The amount and type of food in the stomach also affect the absorption rate; drinking when the stomach is filled is less intoxicating, because foods delay alcohol absorption. Another factor is body weight; the heavier the person, the slower the absorption rate. Studies indicate that sex is a further factor. That is, the stomachs of women contain relatively lesser amounts of an enzyme that breaks down alcohol than do the stomachs of men, so relatively larger amounts of alcohol enter the bloodstreams of women when drinking.
After alcohol passes through the stomach, it is rapidly absorbed through the walls of the intestines into the bloodstream and carried to the various organ
systems of the body, where it is metabolized. Although small amounts of alcohol are processed by the kidneys and lungs and are secreted in the urine and exhaled in the breath, respectively, most of the alcohol is metabolized by the liver. As the alcohol is metabolized, it gives off heat. The body metabolizes alcohol at about the rate of three-fourths of an ounce to one ounce of whiskey an hour. In a technical sense, it is possible to drink at the same rate as the alcohol is being oxidized out of the body. Most people, however, drink at a rate faster than this.
Alcohol's depressant effect on the central
nervous system is dependent on the blood-alcohol concentration (BAC); when it reaches 0.04%Ñ0.04 gram of alcohol per 100 cubic centimeters of bloodÑbrain functioning begins to be negatively affected. With a concentration of 0.20% (a level obtained from consuming 8-10 drinks), a person has difficulty walking and controlling emotions. When the blood-alcohol content reaches about 0.30%, as when a person rapidly drinks about a pint of whiskey, the drinker will have trouble comprehending and may become unconscious. At levels from 0.35% to 0.50%, the brain centers that control breathing and heart action are affected; concentrations above 0.50% may cause death.
Moderate or temperate use of alcohol is not harmful, but excessive or
heavy drinking is associated with alcoholism and numerous other health problems. The effects of excessive drinking on major organ systems of the human body are cumulative and become evident after heavy, continuous drinking or after intermittent drinking over a period of time that may range from 5 to 30 years. The parts of the body most affected by heavy drinking are the digestive and nervous systems. Digestive-system disorders that may be related to heavy drinking include cancer of the mouth, throat, and esophagus; gastritis; ulcers; cirrhosis of the liver; and inflammation of the pancreas. Disorders of the nervous system can include neuritis, lapse of memory (blackouts), hallucinations, and extreme tremor, or delirium tremens ("the DTs"), which may occur when a person stops drinking after a period of heavy imbibing. Permanent damage to the brain and central nervous system may also result. Pregnant women who drink may give birth to infants with fetal alcohol syndrome.
The combination of alcohol and drugs, such as commonly used sedatives and tranquilizers, can be fatal even when the doses, taken separately, would not have a lethal effect. Drugs to counter the effects or aftereffects of alcohol on the body have also been investigated. One such drug, named Ro15-4513, was found to block the behavioral effects of alcohol without altering the metabolism or lowering blood alcohol levels. Because of the ethical problems of such a drug, it has not been developed for commercial use.