Experts Urge End to Daylight Saving Time Amid Health Concerns

As the United States prepares for the end of Daylight Saving Time (DST), a growing number of scientists and experts are advocating for the permanent elimination of the practice, citing significant health and safety risks associated with the biannual clock change.

The debate over DST has intensified as countries worldwide increasingly abandon the tradition. In the last decade alone, nations such as Azerbaijan, Iran, Jordan, Namibia, Russia, Samoa, Syria, Turkey, Uruguay, and most of Mexico have ended their observance of DST. Currently, only about a third of countries globally continue the practice, with the remaining 139 maintaining a single, consistent time zone year-round.

Britain, for example, first implemented DST in 1916 during World War I to conserve fuel by maximizing daylight hours. An experimental period from 1968 to 1971 of remaining on British Summer Time year-round was ultimately abandoned due to complaints about dark winter mornings, particularly in northern Scotland. Now, the UK finds itself among a dwindling number of nations, primarily in Europe, that still shift their clocks.

Even within regions that traditionally observe DST, notable exceptions exist. In Australia, DST is not observed in Queensland, the Northern Territory, Western Australia, Christmas Islands, or the Cocos Islands. Chile adjusts its clocks seasonally, except in the Aysén and Magallanes districts. Mexico abolished DST in 2022, though some border regions maintain the practice to align with U.S. time zones.

The United States presents a complex scenario, observing DST everywhere except Hawaii and most of Arizona. Arizona's exemption stems from concerns that extending daylight into the evening would exacerbate heat and increase energy costs for air conditioning. The Navajo Nation, however, does observe DST to remain synchronized with tribal lands in neighboring New Mexico and Utah.

Experts point to a growing body of research indicating adverse effects from the clock changes. Professor Jagdish Khubchandani of New Mexico State University states that the biannual shift can induce a "mini jet-lag" state, disrupting the body's finely tuned sleep schedules. Studies have reported sharp increases in heart attacks and strokes, along with temporary disruptions in blood pressure, heart rate variability, and stress hormone production.

Health and Safety Impacts

For mental health, changes in mood and episodes of depression have been noted. Research also suggests that individuals with pre-existing mental health conditions face a greater risk of adverse changes following clock shifts. A Swedish study indicated a 10% rise in the use of psychoactive substances, comparable to increases observed after serious injuries or car accidents in the U.S.

Furthermore, scientists have identified a correlation between clock changes and an increase in errors, including traffic accidents. Some studies suggest a roughly 6% increase in fatal traffic accidents following the spring transition to DST.

When clocks "spring forward," studies have linked the shift to an increase in heart attacks and fatal traffic accidents, though also to a decrease in certain types of crime. Conversely, the "fall back" in autumn has been associated with a reduction in all-cause mortality and workplace accidents, but an increase in crimes involving physical harm.

Sleep experts explain that these impacts arise because the body's internal clock, which regulates sleep, hormones, metabolism, and mood, is disrupted. Dr. Jeffrey Kelu, an expert on circadian rhythms from University College Dublin, notes that while social time shifts abruptly, the body clock adjusts gradually, leading to a feeling of being out of sync for days. The key regulator for the body clock is morning sunlight exposure, which facilitates slow adaptation to natural day-night cycles.

Calls for Permanent Standard Time

Many scientists advocate for a single, permanent time zone system that aligns more closely with the sun's natural cycles. Dr. David Kuhlmann, a sleep medicine physician and spokesperson for the American Academy of Sleep Medicine, supports eliminating seasonal clock changes in favor of permanent standard time, arguing it best aligns with the body's natural circadian rhythm. Permanent DST, he cautions, could lead to darker mornings and more evening light, disrupting sleep patterns.

While the UK's brief experiment with year-round DST was discontinued due to concerns about dark winter mornings, the ongoing debate centers on balancing these concerns with the documented negative impacts of seasonal clock changes.