Having as few as five sips of water an hour while driving is equivalent to being over the drink drive limit.
Drivers make more than twice as many mistakes when they are just mildly dehydrated, according to new research. The study revealed that drivers who had only had 25ml of water an hour made more than double the number of mistakes on the road than those who were hydrated - the same amount as those who have been drink driving.
Professor Ron Maughan, Emeritus Professor of Sport and Exercise Nutrition, who led the study at Loughborough University, said: "We all deplore drink driving, but we don't usually think about the effects of other things that affect our driving skills, and one of those is not drinking and dehydration. There is no question that driving while incapable through drink or drugs increases the risk of accidents, but our findings highlight an unrecognised danger and suggest that drivers should be encouraged to make sure they are properly hydrated."