Anyone planning to drive this Christmas has been issued a warning that could save their lives.
Shocking new research suggests that half of drinkers believe they are safe to drive despite exceeding the legal alcohol limit.
The number of people killed or seriously injured (KSI) in drink-drive crashes reached an eight-year high in Britain in 2019, according to Department for Transport figures.
READ MORE: People urged to lock doors and windows as CCTV footage emerges
There were around 2,050 KSI casualties in collisions where at least one driver was over the legal alcohol limit, an 8% increase on the previous year.
Some 6,730 motorists were caught above the legal limit, or on drugs, during UK police forces' annual Christmas-time operation in 2020.
UK police forces are now intensifying enforcement of drink and drug-driving rules in the lead-up to Christmas.
Dr Kai Hensel of the University of Cambridge, who led the research, said: "A significant number of people might misjudge how drunk they are and consider themselves fit to drive when in fact they have a potentially dangerously high level of alcohol in their blood.”
He added: "The best advice is that, if you're driving, just don’t drink.
"But if you really do feel like a drink, then look into your own alcohol tolerance.
"This differs from one person to the next, depending on your sex, weight and age, and there are some reliable apps out there that can help guide you."
In the study, published in the Harm Reduction Journal, ninety students in Germany were asked to declare when they believed they had reached the country’s drink-drive limit after being given beer or wine.
More than a third (39%) of participants came forward after they had already passed the limit on the first day of the study.
By the second day, this was 53% of participants.
The researchers also noticed that the drunker participants became, the worse they were at estimating their breath alcohol concentration.
Dr Hensel warned this could have "serious consequences" in countries with higher legal driving limits like England, Wales and Northern Ireland.
The academic, who also works for Witten/Herdecke University in west Germany, said: "In countries with legal alcohol limits, it's usually the driver who makes a judgment about how much they've drunk and how fit they are to drive.
"But as we've shown, we are not always good at making this judgment.
"As many as one in two people in our study underestimated how drunk they were – and this can have devastating consequences."
The legal alcohol limit in England, Wales and Northern Ireland is 80mg of alcohol per 100ml of blood.
Nowhere else in Europe has a limit above 50mg/100ml.
The Scottish Government reduced their legal limit to 50mg/100ml in 2014.
