Frequently Asked Questions




Practical guidelines


Understanding alcohol


Drinking problems




What is alcohol?

In chemical terminology, alcohols are a large group of organic compounds derived from hydrocarbons and containing one or more hydroxyl (-OH) groups. Ethanol is the main psychoactive ingredient in alcoholic beverages. Ethanol is produced from the fermentation of sugars or starches by yeast. Under usual conditions, beverages produced by fermentation have an alcohol concentration of no more than 14%. In the production of spirits by distillation, ethanol is boiled out of the fermented mixture and re-collected to create drinks with much higher alcohol concentrations. Apart from its use for human consumption, ethanol is used as a fuel, as a solvent and in chemical manufacturing [1]


Why is it important to reduce alcohol use?

Alcohol use is the world's third largest risk factor for disease and disability. In middle income countries it is the greatest risk. Alcohol is known as a causal factor in 60 types of diseases and injuries and a contributing factor in 200 others. Of all deaths worldwide; 4% are attributed to alcohol [2]. Harmful drinking is one of the foremost underlying causes of disease, injury and violence and impacts the health and welfare of individuals, families, communities and society as a whole [3] 


Who is drinking too much?

Worldwide far more men drink alcohol than women and their health is affected accordingly. Alcohol is the leading risk factor for death in men aged 15-59 years. Worldwide, 6.2% of all male deaths are caused by alcohol, compared to 1.1% of female deaths [2]. This is largely due to the fact that men outnumber women 4:1 in weekly episodes of heavy drinking. Alcohol use shows a unique geographic and gender pattern; highest burden for men in Africa, middle-income countries of the Americas and some high-income countries [4].


Practical guidelines

What is a standard drink?

The following drinks, in normal measures contain roughly the same amount of pure alcohol. Think of each one as a standard drink: 

  • 1 small glass of beer (e.g. 250ml at 5%)
  • A small glass of wine or a small glass of sherry (e.g. 100ml at 12% or 70ml at 18%)
  • A single shot of spirits (whiskey, gin, vodka etc.) (e.g. 35ml at 35%)

The most important thing is the amount of pure alcohol in a drink. Spirits have a higher alcoholic concentration than wine or beer. Therefore, one 330 ml can of beer has about the same amount of alcohol as one 140 ml glass of wine, or 30 ml distilled spirit.

In different countries, health professionals employ different definitions of a standard drink because of differences in the typical serving sizes in that country. The self-help program Drink-Less allows that the size of the standard drinks are adapted by the various countries.


What about homemade alcohol?

Most governments seek to license or otherwise control (and tax) the production and sale of alcohol, although home production of various types of alcoholic beverage may be permitted. Homemade or informally produced alcoholic drinks are mostly fermented from sorghum, millet, maize, rice, wheat or fruits [2]. Alcoholic beverages produced illicitly, notably spirits, often have a distinct identity (e.g. "moonshine.' or "white lightning" in the USA, "poteen" in Ireland, "samogon" in countries of the former Soviet Union) and may be contaminated with poisons (e.g. lead) from the production process [1]. The alcoholic content is often unknown, therefore consumption of these drinks should be avoided. 


How much is too much?

At an individual level it is impossible to define what amount of alcohol is hazardous or harmful. It depends on many personal characteristics, as age, gender, ethnicity, weight, height and physical and mental condition. Epidemiological data suggest that the risks of alcohol-related problems increase significantly when consumption exceeds 20g of pure alcohol per day, (around two standard drinks in many countries) [6]. However these studies are based on research on large groups and don’t predict the effect of alcohol on a specific individual. Many people find substantial benefits in reducing their alcohol consumption further or stopping altogether.

The following groups should not drink alcohol at all:

  • Children and adolescents.
  • Women who are pregnant, want to become pregnant or are breastfeeding.
  • Individuals who plan to drive, operate machinery, or take part in other activities that require attention, skill or coordination.
  • Individuals with certain medical conditions or certain medications.
  • Individuals of any age who have had trouble controlling their drinking in the past. If you are a heavy drinker do not stop suddenly. Use our self-help tool to plan how to cut down gradually [5].


Understanding alcohol

How does alcohol affect you?

Alcohol is a central nervous system depressant that lowers your mood and increases anxiety. It is absorbed rapidly from your gut into your bloodstream. Your liver can only break down a small amount of alcohol from your blood at a time. Individual reactions to alcohol vary and may be influenced by; age, gender, ethnicity, physical health (weight, fitness level, etc), how much food was eaten before drinking, how quickly the alcohol was drunk and use of drugs or medications [8]. The risk level from harmful alcohol use varies with age, sex and other biological characteristics. Some individuals have increased susceptibility to the toxic, psychoactive and dependence effects of ethanol. 


What are the long term effects of alcohol on my brain?

Wernicke’s Encephalopathy (WE) and Korsakoff’s psychosis are both severe brain disorders that can occur in chronic drinkers. They are linked to each other and a term often used for both is Wernicke’s/Korsakoff’s syndrome or alcoholic dementia.

WE is a short-term condition which is characterized by confusion, eye movement problems and loss of control of movement which persists when the person is sober. Those that don’t recover from WE often go on to develop Korsakoff’s psychosis, (although some Korsakoff’s cases are not preceeded by WE).

Korsakoff ’s psychosis is a chronic condition consisting of severe anterograde-amnesia (memory loss of events after the onset of WE) and emotional dampening similar in presentation to dementia (confusingly, it does not feature psychotic symptoms) [9]. 

These disorders are linked to alcohol in that they are due to a deficiency of Thiamine (Vitamin B1). People who drink tend to have poor diets and in addition to this, they have problems absorbing nutrients when they digest food. Thiamine is an essential nutrient that we get from food which enables us to keep certain types of brain cells functioning properly. If we don’t get enough thiamine, these brain cells will begin to die, resulting in brain damage in key areas involved in memory formation and shrinkage of areas responsible for muscle coordination.

It is very important to try to eat a balanced diet including thiamine–rich foods, like meat, whole grain cereals, nuts, beans, peas, and soybeans. In addition, many breakfast cereals are fortified with thiamine. When a drinker engages with treatment services, he or she may be prescribed thiamine supplements to help protect the brain. If the WE is caught early, large doses of thiamine can reverse it.  


What are the health risks of drinking too much?

Harmful drinking is a major avoidable risk factor for neuropsychiatric disorders and other noncommunicable diseases such as cardiovascular diseases, liver cirrhosis and various cancers. Harmful use of alcohol is also associated with several infectious diseases such as HIV/AIDS, tuberculosis and pneumonia. A significant disease burden also arises from unintentional and intentional injuries, including road traffic accidents, violence and suicides [8]. Alcohol-attributable harm is determined not only by the overall level of consumption but also by the drinking pattern (eg by heavy drinking sessions) [10].


Are there any positive effects of drinking alcohol?

The harmful use of alcohol results in approximately 2.5million deaths each year. When the estimated beneficial effects of low levels of alcohol use on some diseases, in some population groups are taken into account, the net loss of life remains as high as 2.25million deaths a year [2]. The risks of drinking follow a J shaped curve with cardioprotective effects shown in certain age groups and situations at very low drinking levels. Given the additional risks such as increased levels of violence and road traffic accidents, from a public health viewpoint, there is no safe drinking level. The overall risks of drinking outweigh potential benefits.


But my drinking only affects me, right?

No. Harmful alcohol consumption is not only risky for the drinker. Other people can be put at risk from traffic accidents or violent behaviour. Death, disease and injury caused by alcohol use have socioeconomic impacts, including a heavy financial and psychological burden on families. There are considerable economic loss to society resulting from harmful alcohol consumption, including costs to the health, social welfare and criminal justice systems, lost productivity, and reduced economic development [3].


Drinking Problems

How do I know if I have a drinking problem?

Drinking is a problem if it causes trouble in your relationships, in school, in social activities, or in how you think and feel. If you are concerned that either you or someone you know might have a drinking problem, take our quiz and use our self-help tool. You could also consult your personal health care provider or other local support groups.


What is alcohol dependence (alcoholism)?

A cluster of physiological, behavioural, and cognitive phenomena in which the use of alcohol takes on a much higher priority for a given individual than other behaviours that once had greater value. A central descriptive characteristic of the dependence syndrome is the desire (often strong, sometimes overpowering) to take psychoactive drugs (which may or may not have been medically prescribed), alcohol, or tobacco [1]. Some people experience withdrawal symptoms when they stop drinking. These may be mild (including headaches, nausea, sweating, tremors) to severe (including confusion, hallucinations and convulsions). These withdrawal symptoms can be reduced by cutting down gradually using our self-help tool and maintaining a healthy lifestyle.

What is binge drinking?

A pattern of heavy drinking that occurs in a period of time set aside for the purpose. Binge drinking is defined as a two-hour period in which blood alcohol concentration (BAC) levels reach 0.08g/dL. This usually occurs when women drink about four standard drinks or men drink about five [11]. 


What is blood alcohol concentration (BAC)?

Blood alcohol concentration is the percentage of alcohol by volume in the bloodstream. The risk of traffic accidents begins to increase at a concentration of 0.04% [12].


Why should I drink less?

Quality of life is affected by the amount of alcohol you drink. If you drink less, your health and quality of life will improve gradually. By cutting down on your drinking you'll improve your health, including lower cholesterol, reduced blood pressure, improved weight control and greater resistance to infections. Your sleeping patterns, sexual relationships and performance at work and daily living may also improve [5]. You may save money from reducing your alcohol use; opening up new opportunities. 


How can I drink less?

Buy less and lighter alcohol than usual, for instance light beer and light wine. Increase your intake of non-alcoholic beverages between drinks. Drink different types of alcohol.

Make sure you eat whenever you drink. Don't drink after midnight. Learn to say “No thanks”, and respect a “No” from others. Try to anticipate and avoid “high-risk situations” like  particular people, parties and/or places where you know you will drink a lot.

Try to engage in non-drinking activities with non-problem drinkers, gaining a hobby or doing things you enjoy that are not related to drinking. Use the support of friends, family and local organizations to help you make the lifestyle changes necessary to stop or cut down your drinking.

You can take the self-test to learn if you drink too much and use the online self-help tool to help reduce your drinking.

You can also consult your healthcare provider. 



  1. World Health Organization Lexicon of alcohol and drug terms. Geneva, 2012 (http://www.who.int/substance_abuse/terminology/who_lexicon/en/)
  2. World Health Organization Global status report on alcohol and health. Geneva, Switzerland, 2011
  3. Resolution WHA 58.26. Public Health Problems Caused by Harmful Use of Alcohol. In Fifty-eigth World Health Assembly. Geneva, 16-25 May, 2005
  4. World Health Organisation Global Health Risks: Mortality and burden of disease attributable to selected major risks, Geneva, 2009
  5. Babor TF & Higgins-Biddle JC Brief intervention for Hazardous and Harmful Drinking. A manual for Use in Primary Care. World Health Organisation, Geneva, 2001
  6. Edwards G et al Alcohol Policy and the Public Good. Oxford University Press, Oxford, 1994.
  7. Centers for Disease Control and Prevention. Alcohol and Public Health - Frequently Asked Questions Atalanta, USA, 2012 (http://www.cdc.gov/alcohol/faqs.htm/)
  8. World Health Organization Global strategy to reduce the harmful use of alcohol; Geneva, 2010
  9. Martin, P. R., Singleton, C. K. and Hiller-Sturmhofel, S. (2003). The role of Thiamine deficiency in alcoholic brain disease. Alcohol research and health. Vol 27, 2, pp134-142
  10. Rehm J et al The relation between different dimensions of alcohol consumption and burden of disease Addiction, 105:817-843, 2010
  11. National Institute on Alcohol Abuse and Alcoholism (NIAAA) Moderate and Binge Drinking, USA 2012 (http://www.niaaa.nih.gov/alcohol-health/overview-alcohol-consumption/moderate-binge-drinking).