Shifting clocks for daylight saving time can disrupt sleep patterns and throw off the body’s natural rhythm. This disturbance is linked to higher risks for metabolic and cardiovascular issues, including diabetes, obesity, and heart disease. This view is supported by experts who study sleep and health at prominent universities in the United States, including Beth Ann Malow, a professor of neurology and pediatrics at Vanderbilt University.
Emerging research indicates that the transition to daylight saving time correlates with negative public health effects. In particular, short-term changes in sleep duration and quality can increase the likelihood of heart-related events and sleep disturbances among young people, according to Malow. The timing and quality of sleep matter for overall health, and the clock change can amplify those risks.
Experts explain that exposure to brighter evening light after the clock shift can suppress melatonin production, the hormone that helps signal sleep. With more evening light, people may stay awake later and experience later bedtimes. Teenagers are especially sensitive to these shifts because their natural circadian rhythms tend to lean toward later sleep schedules, making it harder for them to adjust to the new light-dark cycle.
Research also highlights geographic differences in sleep patterns related to time zones. Some findings suggest that individuals on the western edge of a time zone may experience shorter sleep durations than those on the eastern edge, partly due to later sunrises in western areas. When daylight saving time is in effect, the impact can be more pronounced for communities with longer evening daylight, potentially affecting sleep, weight management, and metabolic health over time.
Overall, the disruption of circadian rhythms during the clock change appears to influence a cascade of biological processes tied to day and night. Circadian rhythms coordinate hormones, metabolism, mood, and immune function. Disturbances can ripple through daily life, affecting alertness, appetite, and physical activity, which in turn relate to long-term health outcomes.
Experts emphasize that understanding these patterns helps clinicians and policymakers assess risks and communicate practical strategies. Small, consistent routines for sleep, daylight exposure, and screen use can support healthier rhythms during transitions. Parents, students, and workers may benefit from adjusting schedules gradually in the days surrounding the time shift to ease the adjustment period.
In the ongoing discussion about daylight saving changes, researchers are exploring biomarkers of sleep loss and recovery to quantify how biological systems respond to extended daylight in the evening. This research aims to improve guidelines for sleep health, school start times, and workplace policies so communities can adapt with fewer adverse effects on well-being.
Ultimately, the consensus among sleep scientists is that while daylight saving time offers certain social and economic benefits, it may temporarily increase vulnerability to sleep disruption and related health risks. Public health messages focus on practical steps to protect sleep quality during the transition and to support healthy routines that resonate across age groups and locations.