A slight speed reduction could prove to be a real life saver for commuters, according to a recent study.

Researchers at Sunnybrook Health Sciences Centre and St. Michael’s Hospital came up with a life-expectancy framework for motorists based on U.S. driving data, computerized modeling and the laws of physics. They suggest that every hour spent driving in North America leads to a 20-minute loss in life expectancy, due to the risk of being involved in a crash.

The study, published Monday in the Journal of Medical Decision Making, suggests drivers can add about three hours a year in overall survival by reducing their speed by just three kilometres per hour (km/h) – a change that would tack a mere three minutes on to the average daily commute.

"When drivers try to 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," said lead investigator Dr. Donald Redelmeier, a staff physician at Sunnybrook Health Sciences Centre who often treats vehicle crash survivors.

"The 20-minute penalty for each hour spent driving ... is completely invisible to most drivers. But it is there lurking in the background, and at the end of the year, it adds up to about 45,000 deaths."

Approximately 3,000 people in Canada and nearly 42,000 people in the U.S. die every year in vehicle crashes.

This study was released the same day two teenagers were killed in a crash in King Township. Police said excessive speed was a factor.

The reduced speed would result in three million fewer crashes causing property damage, one million fewer crashes causing bodily harm and 9,000 fewer deaths in the U.S., the study suggests.

“It's another example of speed. The difference between the next pedestrian fatality and no event whatsoever is usually about one or two seconds of attention,” Redelmeier said. “So these small differences in speeding can really make a huge result in vulnerable road users as well ... That would be another argument to slow down."

With files from the Canadian Press

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