Alcohol - an overview
9-minute read
What is alcohol?
Alcohol usually refers to drinks such as beer, wine or spirits that contain a chemical known as ethyl alcohol (ethanol). It is a mood-changing legal drug that belongs to the class of drugs known as 'depressants'.
This doesn’t mean that alcohol makes you depressed (although it can have this effect). It means that alcohol slows down the central nervous system and inhibits many of the brain’s functions. It also affects almost all of the body’s cells and systems.
When a person drinks alcohol it is absorbed into the blood stream through the walls of the stomach and small intestine, and then rapidly distributed to all parts of the body — including the brain.
Although the rate of absorption can differ depending on a number of factors, including sex, body size and composition, age, experience of drinking, genetics, nutrition and individual metabolism, alcohol generally only takes a few minutes to reach the brain.
The liver is the main body organ responsible for removing alcohol from the bloodstream.
Alcohol is processed at a fixed rate, and it generally takes about 1 hour to break down the alcohol content of 1 standard drink. You cannot remove alcohol from your blood by vomiting, having a cold shower or drinking coffee or other caffeine drinks.
What is a standard drink?
Working out exactly what is a standard drink is not always easy. However, 1 standard drink contains 10g of pure alcohol (equivalent to 12.5ml of pure alcohol), regardless of glass size or type of alcohol (such as beer, wine or spirits).
For example, a 250ml bottle of high-strength pre-mix spirits (7 to 10% alcohol by volume) is equivalent to 1.4 to 1.9 standard drinks. A 285ml glass of full strength beer (4.8% alcohol by volume) is equivalent to 1.1 standard drinks.
Therefore, these 2 drinks represent almost 3 standard drinks, based on their alcohol content.
This is why you must measure standard drinks by the amount of alcohol they contain, and not by the number of glasses that you consume.
Check the label of any bottle, can or cask of alcohol for the number of standard drinks it contains.
You can also use these handy calculators to work out how much you are drinking:
- Standard drink calculator by DrinkWise
- How much are you really drinking? by The Right Mix

How much alcohol can different people drink safely?
No amount of alcohol can be said to be safe. Factors such as gender, age, mental health, drug use and existing medical conditions can change how alcohol affects different people.
If you are a healthy adult, and you limit your drinking to no more than 4 standard drinks on any one day, you will reduce your risk of harm from alcohol-related disease or injury to a low level. If you drink more than this, your risk will increase.
Alcohol use increases the risk of cancers, particularly cancers of the mouth, throat, voice box, oesophagus (food pipe), bowel, liver and breast. Even drinking small amounts of alcohol increases your cancer risk.
Alcohol consumption may also lead to weight gain which in turn can contribute to other types of cancers. The Cancer Council recommends people limit their alcohol consumption to reduce cancer risk.
Pregnant women and women who are planning a pregnancy should not drink alcohol because it increases the risk of harm to the unborn baby.
If you’re breastfeeding, the safest option is not to drink alcohol.
Alcohol and children
A younger person’s body doesn’t cope with alcohol as well as an older person’s body. The younger person’s brain, heart and liver aren’t fully developed and so they are less able to process it. Alcohol can therefore seriously damage a younger person’s health.
In some states, it is an offence to supply alcohol to a person aged under 18 in a private home, unless the young person’s parent or guardian has given permission and the alcohol is supplied in a responsible manner. However, the laws that cover alcohol and children vary between states and change from time to time.
For more information, contact the Alcohol and Drug Foundation.
Each week in Australia, alcohol consumption is responsible for numerous hospitalisations and deaths in teenagers aged 14 to 17 years.
Some useful tips for dealing with teenagers and drinking include:
- setting a good example in your own consumption of alcohol
- talking to your teenager about alcohol laws and the potential consequences of breaking them
- rewarding good behaviour when they show a responsible attitude towards alcohol
- talking to your teenager about how to deal with peer pressure related to alcohol or binge drinking
What is binge drinking?
Binge drinking means drinking heavily on a single occasion, or drinking continuously over a number of days or weeks. A person might be more likely to engage in this behaviour if they feel peer pressure to do so, or if they're feeling awkward or uncomfortable at a party.
Binge drinking also has adverse short-term effects, such as nausea, and carries the risk of injury, both to the person drinking and to others around them. It can also have long-term effects on their health and wellbeing. These effects include significant damage to the brain and liver, physical and psychological dependence on alcohol, and the risk of developing emotional and mental health problems such as depression and anxiety.
Drinking and driving
Driving is a complex task, and people who drink and drive have a much greater chance of having a car accident because they are less able to see moving lights, judge distances or respond to multiple stimuli. Alcohol consumption leads to more road crashes than any other single factor in Australia.
Australian law requires fully licensed car drivers to have a blood alcohol concentration (BAC) of 0.05 or less when driving. Australian police are also able to stop any vehicle at any time to breath test the driver for their BAC.
A BAC is a measurement of the amount of alcohol in your body, expressed as grams of alcohol per 100ml of blood. This means that a 0.05 BAC is the equivalent of 0.05g of alcohol per 100ml of blood.
The laws regarding BAC are different for special licence categories such as learner and probationary drivers, taxi, bus, train and heavy truck drivers. These laws can be found on your state or territory’s police website.
Tips on how to drink responsibly
- Keep an eye on what you’re drinking; set limits for yourself and stick to them.
- Start with non-alcoholic drinks and alternate with alcoholic drinks, or try drinks with a lower alcohol content.
- Eat before or while you are drinking.
- Don’t drink and drive.
- If you are going out in a group, work out who will drive everyone home. If no one wants to be the nominated driver, bring enough money for a taxi.
- Avoid mixing alcohol and medication.
- Understand that your blood alcohol will continue to rise after you have had your last drink. You generally won’t reach your maximum BAC until 45 to 90 minutes after having your final drink.
Resources and support
If you or someone you know needs support or treatment for their alcohol consumption habits, you can contact:
- your doctor
- your local community health service
- DrinkWise
- Alcoholics Anonymous Australia: 1300 22 22 22
- Alcohol and Drug Foundation, DrugInfo: 1300 858 584
- National Alcohol and Other Drug hotline: 1800 250 015. Provides free and confidential advice about alcohol and other drugs. It will automatically direct you to the Alcohol and Drug Information Service in your state or territory
- eheadspace (for youth aged 12 to 25) on 1800 650 890 or chat online
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Last reviewed: October 2020