Alcohol is a small, water soluble molecule that is relatively slowly absorbed from the stomach, more rapidly absorbed from the small intestine, and freely distributed throughout the body. Alcoholic drinks are a major source of energy, for example, six pints of beer contain about 500 kcal and half a liter of whisky contains 1650 kcal. The daily energy requirement for a moderately active man is 3000 kcal and for a woman is 2200 kcal.
Alcohol is a sedative and mild anaesthetic. It is believed to activate the pleasure or reward centres in the brain by triggering release of neurotransmitters such as dopamine and serotonin. Alcohol produces a sense of well being, relaxation and euphoria.
These feelings are accompanied by physiological changes such as flushing, sweating, tachycardia (rapid beating of the heart), and increase in blood pressure. The kidneys secrete more urine. Increasing consumption leads to a state of intoxication, which depends on the amount of drink and previous experience of drinking. Even at a low blood concentration of around 30mg/100ml, the risk of unintentional injury is higher than in the absence of alcohol. In a simulated driving test, for example, bus drivers with a blood alcohol concentration of 50mg/100ml thought they could drive through obstacles that were too narrow for their vehicles.
People become garrulous, elated, and aggressive at concentration above 100mg/100ml, and then may stop drinking as drowsiness supervenes. Hangover includes insomnia, nocturia (passing abnormally large quantity of urine during the night), tiredness, nausea and headache. If drinking continues, slurred speech and unsteadiness are likely at around 200mg/100ml, and loss of consciousness may result. Concentrations above 400mg/100mlcommonly are fatal as a result of ventricular fibrillation, respiratory failure or inhalation of vomit, particularly when drugs have been taken with alcohol.
Drinking alcohol, the most widely used psychoactive drug world wide, can be a pressure, but unless the amount taken by regular drinkers are carefully limited many of the bodies vital organs are at risk.
When some of these are damaged seriously enough by the daily intake of alcohol over a number of years, the health and even the life of the drinker is threatened, warns WHO in one of a series of information sheets on alcohol misuse.
Worldwide, the amount of alcohol related illness puts a considerable strain on national health budgets and uses up funds which are badly needed to prevent and cure other diseases. The natural outcome is likely to be a higher incidence of alcohol related problems, and a further substantial drain on scarce economic and social resources.
Regular drinking can damage any of the organs of the body except the bladder and the lungs. The brain, nerves, liver, muscles, kidney, heart, pancreas, sex organs, gullet, stomach and bowel are all at risk. After heart disease and cancer, alcoholic liver diseases (cirrhosis of the liver) is now the chief cause of death among middle aged men in many developed countries. The chances of survival depend on how soon the sickness is caught.
The brain, which when you drink is literally bathed in alcohol, is now being found by medical experts to functionless well in case of heavy drinkers. One result can be difficulty in walking properly and controlling the muscles. In addition, alcohol is of course a depressant, and drinkers who experience deep depressions often commit suicide. The digestive system is also a prime target of alcohol, and scientists have discovered it is involved in cancer of the mouth, throat and gullet. One reason why heavy drinkers die earlier than other people is high blood pressure, caused by the effect of alcohol. There is also damage to the heart muscles which prevent the heart pumping effectively.
The sex drive in men may be harmed by too much drinking. Sex hormone levels fall, leading to less interest in sex and a less ability to make love, or even impotence. Research among women has been less, but the evidence indicates that their interest also diminishes when they drink heavily.
To combat the health hazards of drinking, different approaches have been adopted including health education and motivation, encouraging people to stay within safe limits when they drink, restricting the availability of alcohol, and imposing a tax large enough to make drink a luxury.