I posted earlier this year about the proposal in the United States Congress to switch permanently to Daylight Saving Time, instead of having to change the clocks twice a year. As I do every year, I noted the problems associated with the bi-annual chore: the waste of time and money commercially; the physical and mental health problems from the changes, especially the loss of an hour of sleep; and the motor vehicle and pedestrian accidents caused by sudden darkness. I observed that the proposal to switch permanently to Daylight Saving Time would, as happened when it was tried in 1974, would cause more accidents, especially for schoolchildren in the morning, as there would be increased darkness as the tradeoff for increased light in the late afternoon.
I post on this first day of the return to Standard Time to expand on the additional reason why it is preferrable to Daylight Saving Time: the disruption to our circadian rhythm. The human brain is aligned with the light from the rising and setting of the sun, which sends signals to it. Thus, the body becomes wakeful with increasing light and sleepy with increasing darkness. The rhythms of people in developed places are already challenged because of exterior and interior artificial light, and also because of viewing electronic screens not long before bedtime. Although switching to permanent Daylight Saving Time would eliminate the particular disruption of the circadian rhythm because of the changing of the clocks twice a year, it would not align with the natural apparent movement of the sun across the sky and thereby exacerbate the modern general disruptions to sleep. Therefore, permanent Standard Time is healthiest because it is aligned closely with the solar movement and thus most conducive to natural wakefulness and sleepiness signals, and thus to restful sleep and energetic wake time.
Because sleep is beneficial to physical and mental health in numerous ways, and also has an affect on motor vehicle accidents, it should be prioritized as a public health goal, instead of compromised even further.
