High temperatures can have repercussions for drivers if they don't drink enough water, claims a UK university study, which showed a similar decline in reactions to being over the drink drive limit.
A UK-based heatwave has shone a spotlight on research by Loughborough University, in 2015, that found mild dehydration can lead to driver errors that are equivalent to those seen when motorists are over the drink driving limit.
Using a panel of male drivers in a simulator, the study found that the number of dangerous driving incidents more than doubled when individuals were dehydrated.
It said this increase in error was similar to what would have been seen if someone was driving under the influence of drugs or alcohol, with dangerous lane drifting and late braking increasing among water-starved motorists.
Ron Maughan, professor of Sport and Exercise Nutrition at the university and chair of the European Hydration Institute Science Advisory Board, 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 under the influence of 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.
'To put our results into perspective, the levels of driver errors we found are of a similar magnitude to those found in people with a blood alcohol content of 0.08 per cent, the current UK legal driving limit.
'In other words drivers who are not properly hydrated make the same number of errors as people who are over the drink drive limit.'
With this week's mini-heatwave, motorists are being urged to recognise the symptoms of dehydration so they don't put themselves and others in unnecessary danger on the roads.
When vehicle leasing company Leasing Options surveyed 1,000 UK motorists it discovered that two-thirds (67 per cent) failed to recognise major signs of dehydration.
This includes slower reaction times, loss of focus and muscle cramps.
And while health authorities suggest people should drink around two litres of water a day to remain hydrated, the survey found that 37 per cent of drivers only drink one litre, with 18 per cent of the panel consuming even less than that.
Iain Temperton, director of communications at Road Safety GB, said: 'Before you start a journey you should make sure your vehicle is prepared but, just as importantly, you should ensure that you are ready and fit to drive.
'Driving on our ever more congested network is a task that requires full concentration.
'Making sure you are fully hydrated is a vital part of that process; the safety of vulnerable road users around you depends upon it.'
According to the poll results, men (62 per cent) are marginally more aware of the dangers of driving while dehydrated than women (55 per cent).
Mike Thompson, sales and marketing director at Leasing Options, added: 'The hot weather can sometimes take us by surprise in Britain.
'Drivers may not think drinking an extra glass of water before leaving the house can affect their driving abilities, but it could decrease chances of an accident.'
- Daily Mail