How alcohol affects your body

Australians love a drink. In fact, more than a quarter of Aussie adults exceed the national recommended guidelines on alcohol consumption.¹

But that extra glass of wine might have more of an impact on your health than you realise.

So, what exactly happens to your body when you drink? And just how dangerous is alcohol?

The ingredient that gives alcohol its ‘kick’ is ethanol, which is produced by fermenting various foods. For example, fermenting grains makes beer and whisky, while fermenting fruit makes wine and brandy.

A range of factors determines how alcohol affects you, such as sex, age and whether you have certain medical conditions.

When you drink, alcohol is absorbed directly into your bloodstream through the walls of your stomach and small intestine. From there, it’s quickly distributed throughout your body and brain. Food in your stomach can slow down the rate of absorption, but it won't necessarily stop you from getting drunk.

While alcohol enters your system quickly, it takes much longer to leave. The liver can take about an hour to break down the alcohol in one standard drink, and nothing will hurry that up (including drinking coffee, taking cold showers or vomiting).²

Drinking large amounts of alcohol can lead to many serious, potentially fatal health problems. These include:

• cancer (such as oesophageal, colorectal and liver cancer)³
• heart disease or stroke
• brain injury
• alcohol poisoning
• accidents (such as car crashes and falls).

Excessive drinking can also lead to serious liver diseases. One of the liver’s main functions is to break down toxins, like alcohol, to help remove them from your body. Although the organ can manage small amounts of alcohol, long-term heavy drinking can eventually cause liver damage.

This damage can lead to conditions like fatty liver disease⁴ and alcoholic hepatitis⁵. These diseases are often reversible, but if the liver becomes chronically inflamed it can lead to potentially fatal liver scarring (known as cirrhosis⁶).

While cirrhosis isn’t reversible, you may be able to prevent more damage and help your liver recover by going alcohol-free.

If you choose to drink, it's a good idea to keep within the Australian alcohol guidelines⁷, which for healthy adults includes:

• no more than 10 standard drinks a week
• no more than 4 drinks on any one day.

Those under 18 should not drink alcohol at all.

While there is a yes-and-no side to this question, the answer is mostly no.

For middle-aged people, drinking any type of alcohol, like red wine, may have some benefit for the heart. But you can get similar health benefits from habits like regular exercise, not smoking and sticking to a heart-healthy diet.

And as there’s no ‘safe’ level of drinking, the less alcohol you drink the lower your risk of harm.

For young adults over 18, there isn’t any health benefit linked to drinking alcohol.

A person’s blood alcohol concentration (BAC), the percentage of alcohol in their blood, will almost always be higher after drinking the same amount for women and people assigned female at birth than men and those assigned male at birth.

This is because, compared to men they:

• usually have smaller bodies with less water, meaning alcohol can become more concentrated
• generally have smaller livers.

This means they’re often more likely to get drunk faster than men and recover from drinking more slowly. Unfortunately, it also means that they may develop liver damage and other health problems after lower levels of drinking than men.

To prevent harm to their unborn child, people who are pregnant or planning a pregnancy should not drink alcohol. For people who are breastfeeding, not drinking alcohol is the safest option for your baby.

While a few drinks might make you feel like you’re ready to take on the world, alcohol is a depressant. And the more you drink, the more it affects your brain by slowing your reflexes and affecting your judgement, coordination, and balance.

Regularly drinking above the guideline limits can eventually damage your brain and may lead to alcohol-related brain injury. Symptoms of this include memory, thinking and physical coordination problems.

Heavy alcohol use can cause also:

• damage and kill your brain cells
• affect your metabolism, heart function and blood circulation
• lead to accidents that may injure your brain.

People under 15 are at the highest risk of harm from drinking alcohol, and the current advice is that they should not drink it at all. This is because an adolescent’s brain is still developing, making it more easily harmed by alcohol.⁸

Worryingly, while teenagers are more vulnerable than adults to alcohol’s effects, they also tend to be less easily sedated or disoriented by it. This means teens can often stay awake and drink for longer than adults, which may partly explain adolescent binge drinking.

As you get older, you may not be able to tolerate alcohol as well as when you were younger, so a beer in your 60s may affect you differently from the one you had in your 30s.⁹

When you age, the total amount of water in your body tends to decrease. This can lead to higher alcohol concentrations when you drink, getting you drunker faster.

Older people are also more likely to be on regular medication, which can interact with alcohol and cause side effects.

The Alcohol and Drug Foundation has more information and resources.

The Alcohol and Drug Information Service (ADIS) has a national hotline on 1800 250 015 and provides a 24/7 confidential telephone counselling service.