Permanent DST: Experts Warn of Health Risks

The debate around making daylight saving time (DST) permanent is gaining traction, with recent legislative progress in the U.S. House of Representatives. However, sleep experts like Dr. Wendy Troxel emphasize that science does not support permanent DST.

Instead, evidence strongly favors permanent standard time, often called the "winter clock." Standard time is more closely aligned with human circadian biology, ensuring our internal clocks remain in sync with natural light and darkness cycles. Permanent DST, conversely, shifts sunlight from morning to evening, leading to significant health and safety costs.

During the early 1970s, the U.S. experimented with permanent DST. This initiative was short-lived, repealed within a year due to public backlash over darker winter mornings, increased morning accidents, and a lack of proven energy savings. Commuting to work and school in darkness proved unpopular and detrimental.

Permanent DST forces many to wake before sunrise, creating a chronic misalignment between the body's internal clock and the external environment. This chronic misalignment can lead to widespread sleep deprivation, intensify issues like "bedtime procrastination," and negatively impact mental health, particularly in populations like teenagers who are already experiencing a mental health crisis.

While later evening daylight is often desired for recreation and mood, experts stress that morning light is crucial for regulating sleep, alertness, and mental well-being. Sacrificing this essential morning light under permanent DST poses a substantial public health risk, potentially exacerbating seasonal mood challenges and sleep disorders.