Most of the alcohol a person drinks is metabolised (broken down) by the liver. But it can only break down about 8g of alcohol an hour in an average adult - that's around 1 unit of alcohol (one standard drink) an hour.

Because the liver is the main organ breaking down alcohol, it's also one of the first parts of the body to be harmed by heavy drinking. Long-term drinking kills off liver cells, leading to a disease called 'cirrhosis'. Long-term excessive drinking can also lead to liver cancer.