thumb|400x400px|United States standard drinks of [[beer, malt liquor, wine, and spirits compared. Each contains about 14 grams or 17.7 ml of ethanol.]]

A standard drink or (in the UK) unit of alcohol is a measure of alcohol consumption representing a fixed amount of pure alcohol. The notion is used in relation to recommendations about alcohol consumption and its relative risks to health. It helps to inform alcohol users. Many government health guidelines specify low to high risk amounts in units of grams of pure alcohol per day, week, or single occasion. These government guidelines often illustrate these amounts as standard drinks of various beverages, with their serving sizes indicated. Although used for the same purpose, the definition of a standard drink varies very widely from country to country.

Labeling beverages with the equivalent number of standard drinks is common in some countries.

Definitions in various countries

The definition of what constitutes a standard drink varies very widely between countries, with what each country defines as the amount of pure alcohol in a standard drink ranging from 8 to 20 grams (10 to 25 ml).

The sample questionnaire form for the World Health Organization's Alcohol Use Disorders Identification Test (AUDIT) uses , Some countries choose to base the definition on mass of alcohol (in grams) while others base the unit on the volume (in ml or other volume units). || 10 || 12.7 || || ||

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| Austria || 20 || 25.3 || || ||

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| Benin || 13.6 or<br>13.45 or<br>13.5|| 17.2 or 17

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| Costa Rica || 12 || 15.2 || || ||

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| France|| 11 || 13.8 || || || Standardglas defined as containing 10–12 g (central value used here)

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| Guyana || 10 || 12.7 || || ||

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| Hungary || 17 || 21.5 || || ||

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| Iceland || 8 || 10 || || || áfengiseining defined as 8 g but treated as equivalent to 10 mL

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| Ireland || 10 || 12.7 || || ||

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| Italy|| 19.75 || 25 || || || "".<br>MHLW's conventional unit,<br>based on 1 gō (unit) ( mL) of sake. to align with the WHO AUDIT,<br>and to avoid the conventional "" (20 g)<br> which gave a false impression of "minimum amount to drink".<br>Sometimes this amount (around 10 g) is also called "", a term which traditionally meant 20 g. || 10 || 12.7 || || ||

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| North Macedonia

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| Switzerland

|10

|12.7

|1

|

|

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| Ukraine || 8 || 10 || || || unit of alcohol defined as 10 mL but treated as equivalent to 8 g.

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| United States || 14 || 17.7 || || || standard drink defined as pure ethanol, approximately 14 g

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| Uruguay For example, in the United States, a standard drink is defined as of ethanol per serving, which is about 14 grams of alcohol. This corresponds to a can of 5% beer, a glass of 12% ABV (alcohol by volume) wine, or a so-called "shot" of spirit,), hence will be more than a standard drink. Similarly, although 40% ABV is standard for spirits, the amount of spirit in a mixed drink varies widely.

Beers

  • Half an imperial pint of beer with 3.5% ABV contains almost exactly one UK unit; however, most beers are stronger. In pubs in the United Kingdom, beers generally range from 3.5 to 5.5% ABV, and continental lagers start at around 4% ABV. An imperial pint of such lager (at 5.2% ABV) contains almost 3 units of alcohol rather than the oft-quoted 2 units.
  • Stronger beer (6–12%) may contain 2 UK units or more per imperial half pint.
  • A half-litre (500&nbsp;ml) of standard lager or ale (5%) contains 2.5 UK units.
  • One litre (1000&nbsp;ml) of typical Oktoberfest beer (5.5–6%) contains 5.5–6 UK units of alcohol.
  • A beer bottle is typically between , approximately 1.7 UK units at 5%.
  • can of light beer (2.7% alcohol) = 0.8 Australian standard drinks
  • can of mid-strength beer (3.5% alcohol) = 1 Australian standard drink
  • can of full strength beer (4.8% alcohol) = 1.4 Australian standard drinks
  • of 5% ABV beer = 1 US standard drink

Wines

thumb|upright|A large (250&nbsp;ml) glass of 12%&nbsp;ABV red wine has about three UK units of alcohol. A medium (175&nbsp;ml) glass has about two UK units.

  • A "medium" glass ( of 12% ABV wine contains around 2.1 units of alcohol. However, British pubs and restaurants often supply larger quantities (large glass ≈ ), which contain 3 units. Red wines often have a higher alcohol content (on average 12.5%, sometimes up to 16%). Even though the sizes of wine glasses are defined in UK law, the terms large, medium, standard, etc. are not defined in law.
  • A bottle of 12% ABV wine contains 9 units; 16% ABV wine contains 12 units; a fortified wine such as port at 20% ABV contains 15 units.
  • glass of wine (13.5% alcohol) = 1 Australian standard drink
  • glass of wine (13.5% alcohol) = 1.5 Australian standard drinks
  • One glass of 12% ABV table wine is one US standard drink.

Fortified wines

  • A small glass () of sherry, fortified wine, or cream liqueur (≈20% ABV) contains about one unit.

Spirits

Most spirits sold in the United Kingdom have 35%-40% ABV. In England, a single pub measure () of a spirit contains one unit. However, a larger measure is increasingly used (and in particular is standard in Northern Ireland), which contains 1.4 units of alcohol at 40% ABV. Sellers of spirits by the glass must state the capacity of their standard measure in ml.

In Australia, a shot of spirits (40% ABV) is 0.95 standard drinks.

In the US, one shot of 80 proof liquor is , which is one US standard drink.

Mixed spirits and alcopops

  • can of pre-mix spirits (approx. 5% alcohol) = 1.7 Australian standard drinks
  • can pre-mix spirits (approx. 7% alcohol) = 2.4 Australian standard drinks
  • According to Alcohol and You Northern Ireland resource website, "Most alcopops contain 1.1–1.5 units per bottle. For example, a normal bottle of WKD contains 1.1 units, whereas Bacardi Breezer and Smirnoff Ice both contain 1.5 units of alcohol."

From 1992 to 1995, the UK government advised that men should drink no more than 21 units per week, and women no more than 14. (The difference between the sexes was due to the typically lower weight and water-to-body-mass ratio of women). The Times claimed in October 2007 that these limits had been "plucked out of the air" and had no scientific basis.

This was changed after a government study showed that many people were in effect "saving up" their units and using them at the end of the week, a form of binge drinking. Since 1995 the advice was that regular consumption of 3–4 units a day for men, or 2–3 units a day for women, would not pose significant health risks, but that consistently drinking four or more units a day (men) or three or more units a day (women) is not advisable. These guidelines were updated in August 2016 by the Chief Medical Officers of each of the four regions of the UK. The emphasis shifted from a level that does not pose risk towards levels that pose a low risk. This shift in emphasis was on the basis of an evaluation of evidence about the levels and types of health harm from alcohol. In brief, the weekly guideline was no more than 14 units for both men and women, ideally spread evenly over three or more days, with alcohol-free days included. On a single occasion, the emphasis was on limiting drinks on a single occasion, and not drinking at all during pregnancy. Subsequently, research has suggested that the level of consumption that minimises health loss is zero, i.e. to protect health, it is better not to drink alcohol. However, a 2025 review by the National Academies of Sciences, Engineering, and Medicine concluded that while heavy alcohol use is clearly harmful, moderate alcohol consumption was associated with lower all-cause mortality compared to never consuming alcohol.

Relation to blood alcohol content

As a rough guide, it takes about one hour for the body to metabolise (break down) one UK unit of alcohol, 10&nbsp;ml (8&nbsp;grams). However, this will vary with body weight, sex, age, personal metabolic rate, recent food intake, the type and strength of the alcohol, and medications taken. Alcohol may be metabolised more slowly if liver function is impaired.

Labeling

thumb|right|Example of Wine Bottle label in accordance with UK voluntary health labelling scheme

Australia introduced standard drink labelling in the 1990s, and New Zealand followed with a labelling requirement starting in 2002. The labels were criticized for being too small to read. A focus group study found that most student drinkers used the labels to choose stronger drinks and identify the cheapest method of getting drunk, rather than to drink safely.

: "We will ensure that over 80% of products on shelf (by December 2013) will have labels with clear unit content, NHS guidelines and a warning about drinking when pregnant."

At the end of 2014, 101 companies had committed to the pledge labelling scheme.

  1. Chief Medical Officer's daily guidelines for lower-risk consumption
  2. Pregnancy warning (in text or as a graphic)
  3. Mention of "drinkaware.co.uk" (optional)
  4. Responsibility statement (e.g., "please drink responsibly") (optional)

: Further detailed specifications about the labelling scheme are available from the "Alcohol labelling tool kit".

Drinks companies had pledged to display the three mandatory items on 80% of drinks containers on shelves in the UK off-trade by the end of December 2013.

Studies published in 2021 in the UK showed that the label could be further enhanced by including pictures of units and a statement of the drinking guidelines - this would help people understand the recommended limits better.

See also

  • Alcoholic spirits measure

Notes

References

  • Online converter between different countries' standard drinks and units
  • Drinkaware
  • NHS Choices: Drinking and alcohol
  • NHS Choices: Alcohol unit calculator (archived 21 February 2015)
  • Online alcohol demotivator calculator