Whether we're "falling back" or "springing forward," anyone with children or pets - or frankly, a well-tuned internal clock - will tell you, that first day is usually a doozie. It even has a name: "social jet lag." The American Academy of Sleep Medicine (AASM) says it's time to put daylight saving time to bed.
"When you have a miss-alignment between the timing of your own body clock and what the rest of the world wants you to do, they call that 'social jet lag.' You didn't get to fly to Europe or go anywhere but you get the negative effects," explains Ann Romaker, MD, with the UC College of Medicine Division of Pulmonary, Critical Care and Sleep Medicine and the director of the Sleep Medicine Center at the UC Medical Center.
In a position statement published in the Journal of Clinical Sleep Medicine, the AASM reports there are negative health effects associated with switching to daylight saving time, including increased risk of stroke, cardiovascular deaths, myocardial infarction, hospital admissions from acute atrial fibrillation and more.
Social jet lag is shown to be associated with increased risk of obesity, metabolic syndrome, cardiovascular disease and depression, according to research cited by the AASM. Switching to DST permanently, as some people would prefer, isn't advised because it's "less well-aligned with intrinsic human circadian physiology," says AASM.
Sure, you get more hours of daylight into the evening, but you still have to get up at the same time, meaning less sleep.
When the country switches to daylight saving time in the spring, Dr. Romaker says research shows there's "more inflammatory chemicals running loose in the body. There's lower tone of the vagus nerve, which is the one that controls the heart and swallowing so there's a higher heart rate and higher blood pressure and reduced sleep during daylight saving time in the summer," she says. "In the fall when you go backwards, that's been associated with mood disturbances and increased rates of suicide; traffic accidents increase in the first few days after the change, and fatal crashes increase 6% in the United States."
There's also more stock market volatility on the Mondays following time changes.
For Dr. Romaker, school safety is the biggest reason to stay on standard time year-round.
"When you have kids going to school in the dark in the morning, there's clear evidence that there's a much higher incidence of car accidents involving children," Romaker says. "We come home from work in the dark in standard time but we're a little more used to that and the kids aren't on the road. We do better with driving and accident rate when we follow the standard schedule."
Why Do We Change The Clocks?
NPR reported earlier this year that an AP-NORC Center for Public Affairs Research poll from this time last year found 71% of respondents favor ditching the switch, with 40% of respondents preferring year-round standard time to 31% for year-round daylight saving time.
Daylight saving time in the United States dates to 1918, and was clarified by the 1966 Uniform Time Act. The idea is that daylight saving time saves energy. However, NPR and the AASM point out there's no clear evidence this is actually the case. The U.S. Department of Transportation suggests daylight saving time means more people commute in daylight, reducing traffic incidents, and it lowers crime because more people are out "conducting their affairs during the daylight rather than at night, when more crime occurs."
According to a report by the Congressional Research Service updated Sept. 30, 2020, more than 45 states since 2015 have proposed legislation to change the observance of daylight saving time.
Year-round daylight saving time has been enacted twice in U.S. history. It occurred in 1942, when it was considered "War Time." That ended in September 1945 following the end of World War II. The second occurrence was prompted by the 1973 oil embargo. Congress enacted trial periods of year-round daylight saving time from 1974-1975.