Changing the clocks twice a year is intended to save energy, but there is a growing consensus that the change – which next occurs November 1 in the US – comes at the cost of human lives.
The shifts disrupt our sleep schedules and harm our health, according to experts at the American Academy of Sleep Medicine. And in August, more than a century after daylight saving time was introduced, the AASM released a position statement calling for it to be canceled altogether.
“We’ve had evidence slowly building up over the years, in terms of the adverse effects when we move from daylight saving time to standard time, and vice versa,” said AASM President Dr. Kannan Ramar, a sleep medicine specialist at the Mayo Clinic, told CNN.
Those impacts are widely varied, and include bad news for cardiovascular health; stroke and atrial fibrillation; medication errors; mental health; and traffic accidents. The effect on health is significant. Total mortality went up 3% in Vienna during the week following the springtime transition to daylight saving time, found a recent study in the International Journal of Environmental Research and Public Health that analyzed data from 1970 to 2018.
“It’s like filling a cup with water,” said Ramar, explaining the timing of the AASM’s call to end daylight saving time now. “You fill the cup with water as evidence continues to build up. At a certain point, it tends to overflow.”
“From a sleep science perspective, (changing the clocks) doesn’t make any sense,” agreed Dr. Rafael Pelayo, a sleep specialist with the Stanford Sleep Medicine Center. “Biologically it doesn’t make any sense.”
That is because our bodies take days to adjust to an altered sleep schedule. “Even though you’re just getting an hour less of sleep, it takes about five days to get back in sync,” Pelayo said.
It aggravates an existing problem: Many people already miss out on the sleep necessary for good health.
One in three Americans do not get enough sleep on a regular basis, according to the US Centers for Disease Control and Prevention. (It’s even worse for some people of color. More than 45% of Black Americans reported short sleep duration in the CDC study.)
Skimping on sleep goes far beyond dark circles under your eyes. Poor sleep is linked to type II diabetes, heart attack, asthma and depression. A lack of sleep can even shrink your brain. In 2016 the CDC declared the sleep problem a public health epidemic.
Given how important it is to get good sleep, doctors say you shouldn’t wait for the government to deal with daylight savings — there is plenty you can do to promote good rest on your own. When the next time change approaches, the AASM’s Ramar suggested starting early to ease the transition.
“You already know it’s coming,” he said. “A few days to a week prior to that, slowly shifting your schedule to that time frame is going to be helpful.”
In addition, Ramar said transition is a good opportunity to check in on your overall sleep routine, including avoiding digital devices in the evening and limiting afternoon caffeine consumption.
“Following regular sleep hygiene measures during and around these time changes would mitigate some of the adverse effects,” he said.