This Sunday, clocks throughout the nation will be set back an hour as part of the biannual tradition of daylight savings time. While it was infamously proposed by Benjamin Franklin in 1784, daylight savings time was not formally recognized in the United States until President Nixon’s Daylight Saving Time Energy Conservation Act of 1973. Since then, every second week of March our clocks jump ahead an hour and revert back in the first week of November, popularizing the old adage “Spring Forward, Fall Back.” Despite the grade-school rumor, daylight savings time had nothing to do with American Farmers, but rather, was designed to curb energy consumption and grant an extra hour of sunlight in the day.
Over the decades, however, there have been several observable unexpected consequences of daylight savings time, some of which can be fatal. While we may be getting an extra hour of sleep this weekend, come March we will be losing that hour, which has a notable impact on a person’s alertness, focus, and motor skills. All of those impacts can negatively affect a person’s ability to drive and operate a motor vehicle, leading to an increase in motor vehicle injuries and fatalities.
In 1999, researchers at Johns Hopkins University and Stanford analyzed over 20 years of car crash data from the US National Highway Transportation Safety Administration. Researchers found a significant increase in the number of fatal collisions the day after daylight savings time compared to a typical Monday. Similarly, a recent study published in the US National Library of Medicine National Institutes of Health observed data from over 12.6 million car accidents from 2005 to 2016 and discovered a 16% increase in road accidents the day after daylight savings time and a 12% increase on the second day.