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: Examining the Link Between Daylight Saving Time and Public Health

Examining the Link Between Daylight Saving Time and Public Health

Managing Editor

It's that time of year when the leaves change colors, the temperature turns colder, and the amount of daylight we have each day gets a lot shorter. Yes, my friends, it's the end of Daylight Saving Time (DST). We turn our clocks back a full hour this Sunday (officially at 2 a.m.), and although there is the momentary joy of gaining an extra hour of weekend sleep, we also lose an hour of daylight.

The twice a year changing of the clocks has been debated for nearly as long as we've been doing it. Originally, DST was suggested by Benjamin Franklin, in 1784. However, DST was first implemented in Germany in 1916. The idea was that setting the clocks an hour ahead in the spring would allow us to make better use of the natural daylight and conserve energy. But many people question whether there is any real benefit to DST. In practice, we've not seen the energy savings that had been expected.

But setting the energy efficiency debate aside, DST has been associated with public health benefits, such as an increase in physical activity. Researchers from the London School of Hygiene and Tropical Medicine and the University of Bristol just this month released results from a global study suggesting " that permanent adoption of daylight saving could increase the amount of physical activity in children." According to the study, which examined activity levels of 20,000 children between the ages of 5 and 16 in 9 countries, children's daily activity levels were 15 to 20 percent higher on days when the sun set later than 9 p.m. compared to days when the sun set before 5 p.m.

The amount of physical activity one gets is not the only health and safety issue that has been linked to the changing of the clocks. In the spring, we set the clocks forward and lose an hour of sleep. Studies have shown that the Monday after the switch to DST in the spring is one of the deadliest days on the road, with an increase in traffic fatalities of 17 percent.

Meanwhile, a study published in the New England Journal of Medicine in 2008 found a 25 percent increase in heart attacks on the Monday following the switch back to DST. Researchers have found no similar correlation to turning the clocks back an hour in the fall.

So it seems that all of this switching back and forth of the time is possibly doing more harm than the good originally conceived of more than 100 years ago. Do you agree that it would be more beneficial to implement DST all year round? Our health and the health of the public just may depend on it!

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