The level of alcohol consumption that qualifies as alcohol abuse varies considerably. In Canada in 1991, it was consumption of more than 15 alcoholic drinks per week, a puritanical figure in the eyes of some Canadian physicians. A 1993 American study labelled a woman's consumption of 4, and a man's consumption of 5 alcoholic drinks in succession as a drinking binge.
Europe takes a more tolerant view. A 1996 study viewed moderate drinking as imbibing 2 to 4 glasses of wine or small glasses of beer a day. A 1997 French study claimed that 3 to 4 glasses of wine a day greatly reduced development of Alzheimer's disease, without making any inference about the dangers of alcohol abuse.
A practical definition is that an alcoholic seriously abuses alcohol and drinks intoxicating amounts of alcoholic beverages several times a day on a regular basis. Alcoholics are excessive drinkers whose addiction to alcohol has attained such a degree that there is noticeable mental disturbance or interference with their bodily or mental health, their interpersonal relations, and their smooth social and economic functioning, or they are those people who show the signs of such development. They are unable to recognize the deleterious effects of their habit or, recognizing them, are nonetheless unable to curtail their alcohol consumption and continue in an almost compulsive way to drink heavily.
Alcohol abuse can be distinguished from chronic alcoholism -- which is morbid dependence on alcohol with an easily awakened craving for alcohol, as well as loss of control (shakes and sweating) -- in that the physical and mental complications of the latter only occur in a minority of alcoholics. The complications of alcohol abuse occur primarily in the social sphere. The alcoholic takes alcohol as a mood-altering drug. He/she very early comes to rely more and more on defence mechanisms including, as well as outright denial and rationalizations, the mechanism of projection, namely the ascribing of his own defects to others; thus everything and everybody is wrong, particularly his family who may already suffer at the alcoholic's hands at a time when friends still think him to be a decent and reasonable person. Children's personality development may often be significantly affected by the alcoholic's unpredictable attitude and behaviour, leading to disturbed emotional relations with parents. Complications also occur at work. Alcoholism releases aggression which may be directed against others in anti-social and criminal acts, as well as in traffic accidents.