Let’s be honest: most of us are aware that regularly drinking too much alcohol isn’t great for our health. Maybe you’ve overindulged at a weekend braai and felt rough the next day, or you simply enjoy a few drinks during the week and wonder if it’s impacting your well-being in the long run.
More than just causing unpleasant hangovers, the South African National Department of Health warns that drinking excessively can lead to alcohol dependence and raise your risk of chronic conditions. These include high blood pressure, heart disease, stroke, certain types of cancer, liver and digestive issues, a weakened immune system, and even mental health concerns like depression or anxiety.
And forget the idea that your body treats certain types of alcohol differently. Whether it’s beer, wine, or spirits, your liver only cares about the alcohol they contain. If a drink has a higher alcohol by volume (ABV), it simply means your liver has more work to do.
Given the potential short- and long-term effects of overdrinking, you might be thinking about the best ways to manage your drinking habits. To help, we’ve asked a medical expert to explain how your body breaks down alcohol and how long it remains detectable.
How Your Body Processes Alcohol
According to Dr. Suneet Singh, an emergency physician and medical director at CareHive Health, genetics and your drinking habits both play roles in how your body metabolises alcohol.
Dr. Singh explains that your liver is responsible for processing most of the alcohol you consume, while a tiny amount is digested elsewhere and passes through your system with little effect.
“When you drink alcohol, the process of breaking it down begins in your stomach, thanks to certain enzymes,” Dr. Singh says. “However, most of the alcohol moves quickly to the small intestine, where it’s absorbed into your bloodstream. The alcohol then travels to your liver, which handles over 90% of its breakdown.”
In the liver, alcohol is transformed into a substance called acetaldehyde. This chemical causes many of the unpleasant symptoms experienced after drinking, such as headaches, nausea, and heart palpitations.
How Long Does It Take for Alcohol to Leave Your Body?
Dr. Singh notes that, “A single standard drink (around 340ml of beer, 150ml of wine, or 45ml of distilled spirits) has its maximum impact on your bloodstream roughly one hour after you drink it.”
The body generally needs about five half-lives—where one half-life for alcohol is about four to five hours—to completely clear a drink from the system. “In practical terms, it takes close to a full day for your body to eliminate all traces of just one serving of alcohol,” Dr. Singh adds.
The good news? Most physical symptoms of drinking, like feeling intoxicated, will fade well before your body has metabolised all the alcohol.
How Long Can Alcohol Be Detected in Your System?
Worried you’ll have alcohol in your system the next morning if you need to drive or work? Several factors influence how long alcohol is detectable, including genetics, the amount and strength of alcohol consumed, your age, body mass, overall health, and the test used, Dr. Singh explains.
Typically, alcohol can be found:
- In your blood for up to 12 hours
- On your breath for 12 to 24 hours
- In urine from 12 up to 72 hours
- In saliva from 12 to 48 hours
- In hair for as long as 90 days
Why Alcohol Affects Everyone Differently
Dr. Singh points out that genetics and individual factors influence how quickly your body can break down alcohol. Two key liver enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), play major roles.
“Men typically have higher ADH levels than women,” Dr. Singh says. “Regular drinkers may actually have less ADH compared to those who drink occasionally. Furthermore, about 35-40% of people of East Asian ancestry have lower levels of ALDH, which slows alcohol breakdown.”
If your body produces less of these enzymes, you’ll process alcohol slower and may feel more symptoms like nausea and headaches. The amount and strength of alcohol you consume also affect how long it takes your body to metabolise it.
Alcohol Use in South Africa
South Africa ranks among the countries with the highest per-capita alcohol consumption, and alcohol plays a significant role in road traffic accidents. Research from the Road Traffic Management Corporation shows that alcohol is involved in over a quarter of fatal road crashes.
If you’re planning to drive, remember: the legal blood alcohol limit in South Africa is 0.05g per 100ml for most drivers and just 0.02g per 100ml for professional drivers—almost zero tolerance. Depending on your body size, gender, and timing, even one drink could put you over the limit.
The Bottom Line
The time it takes for your body to clear alcohol—and how it affects you—varies from person to person. Be mindful of how your body reacts after drinking and consider ways to avoid negative short-term effects and the long-term risks of heavy consumption. And if you’re on the road in South Africa, it’s always safest to steer clear of alcohol altogether.
This article was originally published by Emilia Benton on Men’s Health US. Additional reporting and products were contributed by the Men’s Health SA team.
