Everyone knows that drinking too much raises the risk of having a car crash - but research suggests it may also worsen your injuries.
Crashes when drunk were more harmful
Two people involved in identical accidents might suffer a different severity of damage, depending on whether they had been drinking, claim researchers from the University of Michigan.
This is because alcohol may make the body far more vulnerable to impacts.
Studies have suggested it before, but researchers could not be sure that the alcohol-drinking accident victims had not been involved in far more violent crashes.
The latest research covered 1,362 car crashes, and took estimated crash forces into account.
It found that, on a scale of injury severity, alcohol-drinking crash victims were likely to be 30% worse off than their alcohol-free equivalents.
In the UK, 30% of injuries to pedestrian victims of road traffic accidents - and more than half of those to drivers, have been linked by separate research to alcohol consumption.
Dr Ronald Maio, director of the Injury Research Center at the University of Michigan, said: "But acute and chronic alcohol abuse have a number of adverse effects on the body that could conceivably increase the severity of an injury.
Having a designated driver is not completely adequate in protecting you from the harm that alcohol can do
Dr Ronald Maio, University of Michigan
"These include, but are not limited to, effects on the body's blood clotting system that could result in an increased potential for bleeding, a decreased tolerance for low blood pressure or shock, an increase in dangerous heart beats and rhythms from impacts to the chest, and an increase in the amount of injury to particular organs, such as the brain or spinal cord."
He added: "Implications for injury prevention are substantial. Having a designated driver is not completely adequate in protecting you from the harm that alcohol can do if you are involved in a crash."
UK pressure group Alcohol Concern has long campaigned for the legal drinking and driving limit to be reduced, because of evidence that concentration wanes even beyond this lower level.
A spokesman said: "Alcohol is still a factor in hundreds of deaths on the roads.
"It's important we are not complacent about safety gains that have been made in recent years, and keep pressing for more improvements."