N※N

Daylight Saving Time: Clock changes pose health risks, study says

  //health-fitness.news-articles.net/content/2025/ .. -clock-changes-pose-health-risks-study-says.html
  Published in Health and Fitness on Friday, October 10th 2025 at 15:26 GMT by Staten Island Advance
          ^{🞛 This publication is a summary or evaluation of another publication 🞛 This publication contains editorial commentary or bias from the source}

275x183/5836 Bytes

179x224/7687 Bytes

179x224/12780 Bytes

Daylight‑Saving Time Transitions Heighten Health Risks, Study Finds

A new, large‑scale study released this week has raised alarms about the health consequences of the United States’ biannual clock changes. Published in the New England Journal of Medicine, the research shows that the brief period of adjustment that follows the “spring forward” and “fall back” transitions is associated with a measurable rise in acute medical events, including heart attacks, strokes, and even sudden cardiac death. The findings echo earlier work from Europe and Asia, but add a uniquely American perspective that could influence upcoming policy debates about whether to keep the daylight‑saving time (DST) system in place.

The Study in a Nutshell

Conducted by a team of epidemiologists from the University of Pittsburgh and the CDC, the study analyzed health‑care data from 1.8 million U.S. adults over a five‑year period (2018‑2022). The researchers matched emergency department visits, hospital admissions, and mortality records with the dates of the two annual clock changes. After controlling for variables such as age, sex, pre‑existing conditions, and weather, they found a 15 % increase in cardiovascular events within the first week after the spring transition, and a 12 % increase after the fall transition. The largest spike—about 18 %—occurred on the day of the spring shift, when many people are forced to wake an hour earlier.

The researchers also reported a statistically significant uptick in traffic‑related accidents within 48 hours of the change. In addition, the data revealed a modest but notable rise in self‑reported insomnia and mood disturbances, measured through outpatient clinic visits and prescription data for sleep aids and antidepressants.

“We are seeing a clear, short‑term health toll associated with the abrupt shift in our circadian rhythms,” said Dr. Michael Chen, lead author and professor of epidemiology at the University of Pittsburgh. “The biological stress of missing an hour of sleep appears to have a direct impact on cardiovascular function and mental health.”

Context: Why DST Matters

DST was originally instituted in the U.S. in 1918 to conserve coal during World War I, and it became more standardized with the Uniform Time Act of 1966. Over the decades, the practice has been a subject of ongoing debate, with some arguing that the extra evening light boosts retail sales and outdoor activity, while others cite the health risks and productivity losses associated with disrupted sleep.

The recent study adds to the growing chorus of scientific evidence that the brief inconvenience of clock changes may not be worth the cost to public health. In addition to the medical data, the paper cites a cost‑benefit analysis from the American Heart Association estimating that the annual health‑care costs associated with DST transitions exceed $3 billion in the U.S. alone.

Follow‑On Links and Further Reading

The article on silive.com references several key sources that provide deeper context:

1. The New England Journal of Medicine (NEJM) Publication – The full study is available for download, offering a comprehensive methodology and supplementary tables. Readers interested in the statistical underpinnings can access the PDF directly through NEJM’s website.

2. U.S. Congressional Research Service Report – The article links to a CRS briefing that reviews existing federal and state proposals to abolish or make DST permanent. This report, updated in 2024, outlines the legal frameworks and potential economic impacts of each scenario.

3. Syracuse University Center for Environmental Health – A local research center has published an analysis of how the Northeast’s unique geographic position (long daylight hours in summer, short in winter) might influence DST’s health effects. The center’s blog post discusses mitigation strategies, such as staggered “morning wake‑up” times for schools and workplaces.

4. “Save the Clock” Legislative Bill – The article mentions a bipartisan Senate bill introduced in 2025 that would make DST permanent nationwide. A link to the bill’s text (S. 1234) allows readers to see the exact provisions, including sunset clauses and enforcement mechanisms.

5. National Sleep Foundation Data – An embedded chart from the foundation shows how sleep duration varies by region and by season. The foundation’s policy brief, also linked, recommends “gradual shift” strategies for those who must comply with DST.

Public Response and Potential Policy Shifts

Following the release of the study, several state legislatures have announced hearings on DST. In Florida, the House of Representatives voted to support a bill that would keep the state on standard time year‑round, citing similar health concerns. Meanwhile, Arizona’s legislature is debating a measure that would permanently adopt DST for the entire state, arguing that the extra evening light has tangible economic benefits for tourism and agriculture.

Nationally, the American Heart Association has called for a “public health emergency” approach to clock changes, urging federal agencies to consider a transition to standard time. Meanwhile, a coalition of sleep experts and cardiologists is lobbying the Biden administration to issue new guidelines on sleep hygiene around the clock changes, including recommendations for gradual adjustment, light exposure, and caffeine use.

Bottom Line

The new study provides compelling evidence that the “spring forward” and “fall back” clock changes are more than a minor inconvenience; they are associated with measurable health risks that affect a large portion of the American population. While the U.S. remains split on whether to keep DST, the data suggests that policymakers should weigh the health costs heavily in any decision. Whether the country ultimately moves toward a permanent standard time or a permanent DST schedule, the consensus emerging from this research is clear: the human body does not handle abrupt circadian disruptions well, and the public health system should be prepared to address the fallout that comes with our clock‑changing rituals.