Alcohol misuse is a multifaceted problem that includes hazardous use, harmful use, and dependence. Hazardous use, is defined by the World Health Organization, is “a pattern of alcohol consumption carrying with it a risk of harmful consequences,” physical, mental, or social. It includes drinking than the limits recommended by the health authorities or imposed by the law. Harmful use, also called alcohol abuse, involves drinking that is already provoking either physical or mental damage but has not yet led to dependence. Dependence has been described as “the loss of control to abstain from drinking.” An alcohol-dependent person craves alcohol, continues to drink despite various alcohol-induced problems, and suffers from withdrawal in its absence.
No matter what your age, gender, or nationality, you are not free from the risks of hazardous drinking. Just what does alcohol do to the body? What are the health dangers of overdrinking? And what is generally considered a safe level of alcohol consumption?
Ethanol, the chemical compound present in most alcoholic drinks, is a neurotoxin –that is, a substance that can damage or destroy the nervous system. Someone who is drunk is, in fact, suffering from a form of poisoning. In large quantities ethanol causes coma and death. For instance, among students in Japan, the practice of ikkinomi, or alcohol chugging, causes deaths every year. The body is able to convert ethanol into harmless substances, but this is not accomplished immediately. If alcohol is consumed at a faster rate than the body can handle it, ethanol builds up in the system and begins to interfere noticeably with brain function. In what way?
Speech, vision, coordination, thought, and behavior are all connected with an incredibly complex series of chemical reactions in the brain’s neurons, or key cells. The presence of ethanol modifies those reactions, suppressing or enhancing the role of certain neurotransmitters –chemicals that relay signals from neuron to neuron. The stream of information in the brain is thus altered, preventing the brain from functioning normally. That is why when a person drinks too much, he or she develops slurred speech, blurred vision, sluggish movement, and weakened behavioral restraints and inhibitions –all common symptoms of intoxication.
With prolonged exposure to alcohol, brain chemistry adapts to counter the poisonous effect of ethanol and to maintain normal nerve function. This leads to tolerance, whereby the same amount of alcohol has less of an effect than it would have had previously. Dependence occurs when the brain has adapted so much to the presence of alcohol that it cannot operate properly without it. The body craves alcohol to maintain the chemical balance. When a person is deprived of alcohol, his brain chemistry is totally destabilized and withdrawal symptoms, such as anxiety, trembling, or even seizures, set in.
Besides causing modifications of brain chemistry, alcohol abuse can lead to cell atrophy and destruction, altering the brain’s very structure. While partial recovery is possible with abstinence, some of this damage seems to be irreversible. Neurons that die are apparently never replaced, further affecting memory and other cognitive functions. Damage to the brain is not just the result of long-term exposure to alcohol. Research seems to indicate that even relatively short periods of alcohol abuse can be harmful.
The liver plays a vital role in metabolizing food, combating infection, regulating blood flow, and removing toxic substances, including alcohol, from the body. Prolonged exposure damages the liver in three stages. During the first stage, the breaking down of ethanol slows the digestion of fats, causing them to build up in the liver. This is called steatohepatitis, or fatty liver. In time, chronic inflammation of the liver, or hepatitis, set in. While alcohol can cause hepatitis directly, it also appears to lower the body’s resistance to hepatitis B and hepatitis C viruses. According to a study in France, the risk of developing cirrhosis is twice as high in patients infected with hepatitis C virus [HCV] who are heavy drinkers as it is in HCV patients who are moderate drinkers. It is recommended that HCV-positive individuals drink very little alcohol or none at all. If unchecked, inflammation causes cells to burst and die. Compounding this damage, alcohol seems to trigger the natural system of programmed cell death called apoptosis.
The final stage is cirrhosis. The vicious cycle of continuous inflammation and cell destruction causes irreversible scarring. Eventually, the liver becomes lumpy, instead of remaining spongy. Finally, scar tissue prevents blood from flowing normally, leading to liver failure and death.
Alcohol’s effect on the liver has another insidious side effect –the liver is less capable of playing its defensive role in counteracting the effect of cancer-forming agents. In addition to favoring the development of cancer of the liver, alcohol greatly increases the risk of cancer of the mouth, the pharynx, the larynx, and the esophagus. What is more, alcohol makes the mucous membranes in the mouth more easily penetrated by cancerous substances in tobacco, elevating the risk for smokers. Women who drink daily are at a greater risk of breast cancer. According to one study, the risk for those who drank three or more alcoholic beverages per day was 69 percent higher than that of nondrinkers.