Drive Less, Live Longer

Let’s face it: Most motorists just drive too fast. Too many people are in too big a hurry to get where they’re going. Safety experts and law enforcement agencies are constantly admonishing the lead-footed to “Just Slow Down!” And to underscore that point, a recent study by a Canadian research team has determined that driving decreases life expectancy.

According to the study, every hour you spend behind the wheel in North America leads to a 20-minute loss of life expectancy due to the risks of a fatal car crash. Further, the study concluded that by slowing down just two miles per hour, the average driver would increase their life expectancy by three hours per year.

“When drivers speed to get to their destination faster, they actually lose more time because the savings from faster travel are offset by the increased prospect of a crash,” says Dr. Donald Redelmeier, the lead investigator in the study. Redelmeier is a professor of medicine at the University of Toronto and a staff physician at Sunnybrook Health Sciences Centre, Canada’s largest trauma center.

“The study suggests that small changes can have large consequences...and would translate to approximately 3 million fewer property-damage crashes, one million fewer injurious crashes, and 9,000 fewer fatalities each year in the United States,” says Redelmeier, who believes that if North American drivers would slow down by two miles per hour, it could reduce crash-related property damage by about $10 million each day.

Keeping with the old truism that most crashes occur within 25 miles of your home, Redelmeier warns that the chances of being in a fatal car crash are just as high when you’re running errands around town as they are if you’re on a long trip, out on the freeway. “Even a short trip can put you into contact with 100 other drivers, some of whom may be speeding, some of whom may have poor driving skills, and any one of those could ruin your life, forever,” he says.

One sad statistic is that for every person who is killed in a car crash in North America, there are another 50 individuals who suffer crash-related injuries, with 20 of those injuries being permanently disabling, says Reidemeier.

The study was based on a combination of computerized traffic modeling, national statistics covering driving on public roadways, and the laws of physics. The computer models calculated results taking into account average distances and time drivers in the United States spend traveling daily, the number of annual crashes categorized as fatal, injuries and property damage, and the expected time losses due to accidents.

The study was supported by the Canada Research Chair in Medical Decision Sciences, the Canadian Institutes of Health Research, the National Institutes of Health Resuscitation Outcomes Consortium, and the Patient Safety Service of Sunnybrook Health Sciences Centre.

“What inspired this study was what I saw at the hospital. I am always amazed that so many of my patients in the trauma center were injured in crashes that were caused by excessive speed,” says Redelmeier. “And I’m not talking about egregious speeding, like the psycho who is driving 150 miles an hour. I’m just talking about the drivers who are maybe a little over-confident, and are maybe driving a few miles an hour faster than they should be.

“And if you’re someone who frequently drives 80 miles an hour, slowing down to 65 or 70 would result in an even more significant increase in your life expectancy.

Leonard Evans, author of “Traffic Safety,” a popular textbook on the subject, says the results of Redelmeier’s study “are very much in accord” with his own findings. “Speed is the most important factor in traffic safety,” he stresses.

Evans, a retired General Motors research scientist, cites the “three simple laws,” as he calls them, that he spelled out in his book:

“Number one, the faster you drive, the more likely you are to crash,” says Evans. “Number two, the faster you were going, the more likely you are to be injured. And number three, if you’re injured, the faster you were traveling, the more likely you are to be killed.

Redelmeier also stresses that his findings bolster the argument for increasing government efforts to reduce speeding, including photo radar, traffic calming programs, and crackdowns on street racing. "Such programs can have huge gains even if partially effective and imperfectly run," says Redelmeier.

Evans agrees that such government programs and practices need to be implemented and enforced. “There is a great deal of evidence that if you drive just two percent faster, your risk of being killed increases by 10 percent,” he says.

Redelmeier and Evans both believe that the government isn’t nearly pro-active enough in implementing such programs. “The United States lags way behind other countries in terms of programs like red light cameras and photo radar,” says Redelmeier. “The efforts to curb speeding are much more advanced in many other countries.”