New research finds that making daylight saving time permanent could result in at least 2 billion additional dark commutes to school nationwide, raising concerns about pedestrian safety, children’s sleep and academic performance.
Americans will turn their clocks back one hour this Sunday, marking the end of daylight saving time and bringing earlier sunsets as the country moves toward winter.
But the long-running debate over whether the United States should stop changing its clocks has gained new attention following research from the University of Washington, which warns that making daylight saving time permanent could have serious consequences for schoolchildren.
According to the study, permanent daylight saving time could lead to at least 2 billion additional dark morning commutes to school across the country.
Researchers also found that fatal traffic crashes involving school-aged pedestrians are roughly twice as likely to occur during dark morning hours as they are after sunrise.
“These dark mornings will inequitably affect children who have to go to school at a certain time,” said Horacio de la Iglesia, a professor of biology at the University of Washington and a senior author of the study. “Nobody wants their kids to go to school in the dark.”
Why morning sunlight matters
Beyond traffic safety, researchers warn that reduced exposure to morning sunlight could disrupt children’s natural sleep-wake cycles.
Morning light helps regulate the body’s internal clock by suppressing melatonin, the hormone responsible for sleep, while stimulating cortisol, which helps the body become alert and ready for the day.
Insufficient morning light can interfere with sleep patterns, mood and appetite. Experts also warn that disrupted sleep could affect children’s concentration and academic performance.
High school students could be affected the most
The study found that high school students could face the greatest impact because they generally have the earliest school start times.
Children living in the western parts of their time zones could also be disproportionately affected, as sunrise occurs later in those areas.
Researchers examined school start times at more than 16,000 schools across 14 of the 19 states that have already approved legislation supporting permanent daylight saving time.
Their calculations used school schedules, enrollment figures and geographic coordinates to estimate how many students would travel to school before sunrise.
The researchers assumed students would leave home around 8 a.m. However, they noted that this assumption was relatively late and that the actual number of dark commutes could be even higher.
The political debate continues
President Donald Trump and several Republicans have supported making daylight saving time permanent, arguing that changing clocks twice a year is inconvenient and costly.
The U.S. House of Representatives passed legislation supporting the change over the summer, but the proposal remains stalled in the Senate.
Meanwhile, 19 states have already passed laws or resolutions supporting permanent daylight saving time, contingent on federal approval.
Opponents argue that keeping daylight saving time throughout the year would mean darker winter mornings, potentially increasing traffic risks and disrupting children’s health.
The new University of Washington research adds another dimension to the debate, suggesting that the decision to keep clocks forward year-round could have consequences extending far beyond convenience and energy costs.
For now, Americans will continue the twice-yearly clock change, with daylight saving time ending this Sunday.
