Researchers at Loughborough University have discovered that people make more than twice as many mistakes while driving if they are dehydrated.

The study, which was published in the journal Physiology and Behaviour, showed that drivers who had consumed just 25ml of water an hour were prone to making the same amount of mistakes as drink drivers with a blood alcohol content of 0.08%, equivalent to the UK drink drive limit.

During a normal hydration test, drivers carrying out the simulated driving exercise were provided with 200ml of water every hour, compared with a dehydration exercise where drivers were only provided with 25ml of water. During the dehydration test, the number of driving incidents reached 101, more than double the 47 incidents which occurred during the normal hydration test.

Dehydration can cause impaired mental function and reductions in concentration and alertness.

Helen Williams a senior road accident solicitor based in Thompsons Solicitors’ Bristol office, said: “The results of this study provide a fascinating new angle to the dangers we all face when driving and the factors that can affect our ability to drive.

“Before getting behind the wheel, it is absolutely essential that, as the driver responsible for your own safety, and the safety of others, you are fully fit and safe to drive. While everyone accepts that drink and drug driving are highly dangerous and morally reprehensible, it is clear from this study that there are other factors which, without intention, can seriously impair a person’s ability drive.

“The effects of road traffic accidents are long-lasting and life-changing and it makes absolute sense for drivers to take every step they can to protect themselves, and by consequence other road users. This clearly now extends to keeping hydrated and we urge all drivers to ensure that they are in the right condition before getting behind the wheel.”