How long does it take alcohol to leave our system?

You’re probably sensible and wait a while after having a few drinks with your dinner or at a party before getting behind the wheel, but how long does your body actually need to eliminate alcohol?

Alcohol is actually absorbed very rapidly into the bloodstream. On an empty stomach, you can reach the maximum blood-alcohol level just half an hour after drinking, while having drinks with food stretches that to an hour. The time it takes for alcohol to be eliminated from your body, however, is much longer. Waiting an hour or two while chatting over coffee is not enough for it to leave your bloodstream.

Experts typically estimate that your blood-alcohol level drops by 0.1g to 0.15g every hour. These values were first published by a Swedish chemist called Erik Widmark, lending his name to the equation for calculating the rate of blood alcohol content decrease over time – the Widmark curve.

Still, it’s not so clear cut as that, as everyone’s body reacts differently depending on their weight, sex and age. If you want to calculate your own exact rate of blood alcohol elimination, make sure you take your reference measurement (peak blood alcohol content) 30 minutes after your last drink. You should also be aware that there is no proven effective way to speed up the elimination of alcohol from your blood, so put down that 3rd espresso!