Poor sleep is one of the most dangerous risk factors facing South African motorists, with Discovery Insure noting that it can be more dangerous than driving above the legal limit for alcohol. <\/p>\n\n\n\n
Using four years of sleep data from more than 10,000 Discovery Insure drivers, Discovery said that missing sleep over several consecutive nights is one of the strongest drivers of vehicle accident risk. <\/p>\n\n\n\n
\u201cBreathalysers can detect alcohol impairment, a visible and well-understood risk factor for accidents. Driver fatigue, by contrast, has until now been largely invisible,\u201d said Robert Attwell, Discovery Insure CEO. <\/p>\n\n\n\n
\u201cSleep affects concentration, reaction time and decision making, all of which directly influence driving behaviour and outcomes. <\/p>\n\n\n\n
Discovery Insure’s data suggested that poor sleep is also five times more predictive of motor vehicle accident risk than traditional insurance risk factors in isolation, pointing to a major blind spot. <\/p>\n\n\n\n
It added that missing sleep over several consecutive nights, known as sleep debt, has an even greater impact on accident risk.<\/p>\n\n\n\n
Roughly 30% of Discovery Insure drivers accumulate some level of sleep debt while driving, with half of sleep\u2019s overall impact on accident risk linked to chronic poor sleep rather than one isolated night.<\/p>\n\n\n\n
Drivers who maintain less than an hour of sleep debt over three straight nights have up to a 36% lower accident risk than those carrying five or more hours of sleep debt. Other findings include: <\/p>\n\n\n\n
Drivers who also regularly get seven to eight hours of sleep are also roughly 32% less likely to be involved in an accident than those who sleep too little.<\/p>\n\n\n\n
Those who go to bed roughly one hour before their ideal bedtime each night are up to 36% less likely to have an accident than those with irregular sleep patterns.<\/p>\n\n\n\n
Motorists who get adequate Rapid Eye Movement (REM) sleep also experience a roughly 14% lower risk of accidents.<\/p>\n\n\n\n
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<\/a>While the evidence is growing, Discovery said that many drivers underestimate the dangers of driving while tired.<\/p>\n\n\n\n
It said that a 2024 survey<\/a> found that almost 90% of adults would avoid driving after a few drinks, but only 50% said they\u2019d do the same after poor sleep.<\/p>\n\n\n\n