Other drivers admitted to getting behind the wheel without wearing their contact lenses or prescription glasses.
Commenting on the study, Sainsbury's car insurance manager Lucy Hunter said that many motorists may not have fully considered the dangers of their actions.
"It can be easy to become complacent behind the wheel of a car especially when driving regular routes but our advice is to stay alert and safe and don't allow yourself to be distracted," she explained.
Sainsbury's survey has been released days after research by Zurich Insurance found that around one in five motorists leave items worth an average value of £160 in their cars and take no steps to protect them.
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