A sleep expert is raising alarms about the potential health consequences of making daylight saving time permanent in the United States, just days after the House Energy and Commerce Committee advanced legislation supporting the change in a 48-1 vote on May 21, 2026. Dr. Wendy Troxel, a licensed clinical psychologist and senior behavioral scientist at RAND, argues that the science does not support permanent daylight saving time and that permanent standard time would be the healthier choice for Americans.
The Trump administration has expressed support for ending the biannual clock changes by making daylight saving time permanent. However, the American Academy of Sleep Medicine takes a different position, supporting permanent standard time over permanent daylight saving time. This contrast between legislative momentum and scientific consensus has sparked a critical debate about how time changes affect public health.
The Science Behind the Opposition
Dr. Troxel, who is based in Utah, explained that while ending the twice-yearly clock change is welcome, the method matters significantly for public health. She stated that standard time is more closely aligned with human circadian biology, meaning the relationship between light, darkness and internal clocks remains intact.
The expert emphasized that permanent daylight saving time simply shifts an hour of morning sunlight to the evening, and there are significant health and safety costs of that trade. Morning light is crucial to regulate sleep, alertness and support mental health, and this would be sacrificed with permanent daylight saving time, according to Dr. Troxel.
She addressed a common misconception about the appeal of more evening light. More evening light may feel enjoyable, in part because we equate it with lovely summer evenings, but permanent daylight saving time does not mean permanent summer. It just means we will get less morning sunlight and more evening sunlight, Dr. Troxel explained.
What We Know So Far
The House Energy and Commerce Committee advanced the legislation to make daylight saving time permanent with an overwhelming 48-1 vote on May 21, 2026. The Trump administration has indicated support for ending the biannual clock changes through this approach.
Current research shows that springing forward in March is associated with spikes in car crashes, heart attacks and sleep deprivation. Dr. Troxel acknowledged that ending the biannual clock change is something most sleep scientists and the public would welcome. The disruption of springing forward every March is associated with real, measurable harm.
One in three Americans are already getting insufficient sleep, according to the information provided by Dr. Troxel. Under permanent daylight saving time, states like Utah would not see sunrise until about 9 a.m. in winter months, creating challenges for those who need to wake early for work or school.
Historical Context: The 1970s Experiment
The United States has attempted permanent daylight saving time before. In the early 1970s, the country implemented permanent daylight saving time, but the law was repealed within a year. Dr. Troxel noted that the repeal came amid public displeasure with commuting to work and school in the dark and increases in morning car crashes, and with no demonstrable impact on energy savings.
This historical precedent raises questions about whether the current legislative push might face similar challenges if implemented.
Concerns for Teenagers and Mental Health
Dr. Troxel expressed particular concern about how permanent daylight saving time could affect younger Americans. She described the situation as especially alarming for teenagers, a population the U.S. surgeon general has identified as being in a mental health crisis.
The sleep expert illustrated the challenge with a practical example. A teenager who needs to wake at 6:30 a.m. for an 8 a.m. school start time would face significant difficulties under permanent daylight saving time during winter months.
She challenged the notion that more evening light helps combat seasonal depression. Framing permanent DST as a fix for seasonal depression gets the science exactly backwards, Dr. Troxel stated.
The Biology of Circadian Rhythms
Dr. Troxel explained that human biology cannot simply adapt to artificial clock changes. You cannot override that biology by simply shifting external clocks forward. What you get instead is a population that is effectively waking up in the middle of their biological night, every single day, she said.
The American Academy of Sleep Medicine’s support for permanent standard time aligns with this scientific understanding of how human bodies respond to light and darkness. The organization maintains that standard time better supports the natural circadian rhythms that regulate sleep, alertness and overall health.
What Happens Next
The legislation has advanced through the House Energy and Commerce Committee but still faces additional steps in the legislative process. The overwhelming 48-1 vote demonstrates strong support within the committee, though the broader path forward remains to be determined.
Sleep scientists and medical organizations continue to advocate for permanent standard time as the healthier alternative, even as legislative momentum builds behind permanent daylight saving time. The debate highlights a tension between public preferences for longer evening light and scientific evidence about the health effects of chronic circadian misalignment.
Impact on Daily Life
If permanent daylight saving time were implemented, Americans in many parts of the country would experience significantly later sunrises during winter months. In Utah, for example, sunrise would not occur until about 9 a.m. during the darkest parts of the year.
This would mean many workers and students would begin their days in complete darkness, potentially affecting alertness, safety and mental well-being. The concerns about morning car crashes that contributed to the repeal of permanent daylight saving time in the 1970s remain relevant to the current discussion.
Frequently Asked Questions
Why do sleep experts oppose permanent daylight saving time?
Sleep experts argue that permanent daylight saving time would reduce morning sunlight, which is crucial for regulating circadian rhythms, sleep patterns and mental health. Standard time better aligns with human biology.
Has the United States tried permanent daylight saving time before?
Yes, the United States implemented permanent daylight saving time in the early 1970s but repealed it within a year due to public dissatisfaction with dark mornings, increased car crashes and no demonstrable energy savings.
What time would the sun rise under permanent daylight saving time?
In some states like Utah, the sun would not rise until about 9 a.m. during winter months under permanent daylight saving time, meaning many people would wake and commute in darkness.
What does the American Academy of Sleep Medicine recommend?
The American Academy of Sleep Medicine supports permanent standard time rather than permanent daylight saving time, citing better alignment with human circadian biology and health outcomes.
How many Americans currently get insufficient sleep?
One in three Americans are already getting insufficient sleep, according to information cited by Dr. Wendy Troxel of RAND.
The debate over permanent daylight saving time versus permanent standard time continues as the legislation moves through the congressional process. While both approaches would eliminate the biannual clock changes that many Americans find disruptive, the scientific community maintains that the choice between the two options carries significant implications for public health and safety.
