This paper shows that daylight saving time is not a harmless calendar ritual: the clock changes align with measurable spikes in mortality, suicide, cardiovascular events, sleep loss, and road danger, with the spring and autumn transitions carrying distinct risks. Read the full paper to see where the strongest signals emerge, which outcomes remain inconsistent, and why the evidence increasingly points toward ending biannual clock changes rather than treating them as a neutral social habit.
Abstract: To synthesize the multi-dimensional impacts of Daylight Saving Time transitions and chronic exposure on human health, public safety, and societal infrastructure, utilizing evidence from epidemiological, experimental, and retrospective cohort studies. The review utilises 19 original studies with 547949 total participants (topic deduplicated ΣN). The evidence map indicates that daylight saving time is consistently associated with short-term circadian disruption and with measurable signals in health and safety outcomes, particularly around clock-change periods. The clearest recurrent findings include a roughly 3% increase in daily total mortality after the spring transition, a 6.25% rise in suicide rates after the spring shift, a 16% increase in deer-vehicle collisions after the autumn transition, and a median 37-minute sleep reduction among patients with delayed sleep-wake phase disorder during daylight saving time. Across topics, the pattern supports circadian misalignment and sleep loss as plausible shared mechanisms linking clock changes to cardiovascular, mental health, occupational, and traffic-related harms, while also showing that some outcomes remain null or inconsistent. These findings support practical planning by clinicians, emergency services, and policymakers around transition periods and are broadly aligned with calls to reduce biannual clock changes in favor of schedules better matched to human biology. Future research should prioritize standardized, high-validity longitudinal and quasi-experimental comparisons of seasonal clock policies, especially to distinguish the acute effects of transitions from the chronic effects of prolonged daylight saving time exposure.
Keywords: Daylight Saving Time; Circadian Rhythm; Social Jetlag; Sleep Disruption; Traffic Safety; Public Health; Standard Time; Mortality; Occupational Safety; Chronobiology
Review Stats
Final search date and database lock: 2026-03-23 13:44:08 CET
Plan: Pro (expanded craft tokens; source: PubMed)
Source: PubMed
Total Abstracts/Papers: 875
Downloaded Abstracts/Papers: 875
Included original and non-original Abstracts/Papers (all): 31
Included original Abstracts/Papers (Vote counting by direction of effect): 19
Reference Index (links used in paper): 30
Total participants (topic deduplicated ΣN): 547949
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[25] Daylight Saving Time transitions and Cardiovascular Disease in Andalusia: Time Series Modeling and Analysis Using Visibility Graphs. — https://doi.org/10.1177/00033197221124779
