Turning Back the Clocks a Bad Idea, Scholar Says

Daylight saving time ends this weekend in Europe and next weekend in the U.S., but extending it could help couch potatoes get more exercise and might also reduce the incidence of depression, a British social policy scholar argues.

“It must be rare to find a means of vastly improving the health and well-being of nearly everyone in the population; here we have it,” Mayer Hillman, PhD, of the University of Westminster in London, wrote online in BMJ.

“The source of the problem is that on average over the year only one or two of our waking hours in the mornings are spent in darkness whereas nearly half of the 10 to 11 waking hours after midday are in darkness. The critical limiting factor is obviously the onset of dusk.”

He continued, “As most children are restricted from going out after dark, the lighter evenings would enable parents to let them spend more time outdoors. A significant majority of older people impose a curfew on themselves, preventing them from going out after dark, owing to anxiety about assault, and poorer vision and hearing.”

Hillman argued that adding one to two hours of daylight in the evening would more than compensate for the hour lost in the morning. In an e-mail to MedPage Today, he pointed out that, for more than half the year, most people would still be asleep during that hour of extended darkness.

“As far as exercise — less clear — because as we all know, even in the summer many people do not engage in regular exercise. However, it will certainly allow more opportunity to exercise and enhance ability to engage in both social and physical activities,” she wrote.

But he cautioned that putting more daylight into the evening would not necessarily translate into more outdoor exercise, a point made bluntly by another researcher as well.

Hillman’s proposal “assumes that a lack of daylight is somehow a barrier to exercise. I don’t know of any evidence for that,” scoffed Goutham Rao, MD, clinical director of the Children’s Hospital of Pittsburgh’s weight management clinic.

“Americans have plenty of opportunity to exercise indoors, where daylight is less of an issue,” Rao said in an e-mail.

Most research has focused on the short-term effects of resetting the clocks. Several studies have found increases in traffic accidents and workplace injuries the Monday after the spring implementation of daylight saving time. Researchers have blamed sleep loss associated with the hour cut from Sunday morning.

He said the benefit would be greatest around the spring and fall equinoxes rather than during high summer when, he acknowledged, “there is already more than adequate daylight and sunlight.”

“The attractions of more ‘accessible’ daylight hours would be appreciated not only after coming home from work and school but also at weekends,” Hillman said.

“If more sunlight equates to more ‘doing” as opposed to reflecting or stopping to simply be, which has traditionally been a piece of the winter experience, will we lose something?” Read more at www.medpagetoday.com

Daylight Saving Time is four weeks longer since 2007 due to the passage of the Energy Policy Act in 2005. The Act extended Daylight Saving Time by four weeks from the second Sunday of March to the first Sunday of November, with the hope that it would save 10,000 barrels of oil each day through reduced use of power by businesses during daylight hours. Unfortunately, it is exceedingly difficult to determine energy savings from Daylight Saving Time and based on a variety of factors, it is possible that little or no energy is saved by Daylight Saving Time.Read more at geography.about.com