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# Daylight Saving Time Is the Worst


![Jeffrey Kluger](https://static.time.com/v3/assets/bltea6093859af6183b/blt8ba5798889b0f77d/69868efb1eebf78937370d95/jeffrey-kluger.jpg?branch=production&width=3840&quality=75&auto=webp&crop=1:1)

by 

[Jeffrey Kluger](https://time.com/author/jeffrey-kluger/)


![Jeffrey Kluger](https://static.time.com/v3/assets/bltea6093859af6183b/blt8ba5798889b0f77d/69868efb1eebf78937370d95/jeffrey-kluger.jpg?branch=production&width=96&quality=75&auto=webp)

## Jeffrey Kluger


Editor at Large

Mar 7, 2024 3:16 PM UTC

![British Summer Time](https://static.time.com/v3/assets/bltea6093859af6183b/blt95202f5a62760efa/698a49119d83e86256b98a7a/GettyImages-1249504926.jpg?branch=production&width=3840&quality=75&auto=webp&crop=3:2)

President of the British Horological Institute, Alan Midleton, adjusts the time to Daylight Saving Time.

President of the British Horological Institute, Alan Midleton, adjusts the time to Daylight Saving Time.PA Wire/Getty Images

![Jeffrey Kluger](https://static.time.com/v3/assets/bltea6093859af6183b/blt8ba5798889b0f77d/69868efb1eebf78937370d95/jeffrey-kluger.jpg?branch=production&width=3840&quality=75&auto=webp&crop=1:1)

by 

[Jeffrey Kluger](https://time.com/author/jeffrey-kluger/)


![Jeffrey Kluger](https://static.time.com/v3/assets/bltea6093859af6183b/blt8ba5798889b0f77d/69868efb1eebf78937370d95/jeffrey-kluger.jpg?branch=production&width=96&quality=75&auto=webp)

## Jeffrey Kluger


Editor at Large

Mar 7, 2024 3:16 PM UTC

On Sunday, March 10 at 2 a.m., the U.S. and about [a third of the world’s other countries](https://www.pewresearch.org/short-reads/2023/10/26/most-countries-dont-observe-daylight-saving-time/) will set their clocks forward by one hour, which will make the sun seem to rise later in the morning and hang in the sky longer in the evening. [I am not alone in dreading it](https://time.com/6261465/daylight-saving-time-seasonal-affective-disorder/). Plenty of people want nothing to do with the whole hoary practice.

It’s bad for health, bad for safety, bad for your mood, and just plain unpopular. But that doesn’t stop us from changing the clocks, pointlessly, twice a year.

## The ridiculous history of Daylight Saving Time

The first push for changing the clocks took place in 1907, when British builder William Willett [penned a pamphlet](https://time.com/4549397/daylight-saving-time-history-politics/) titled “A Waste of Daylight,” in which he proposed setting clocks forward one hour. “The sun shines upon the land for several hours each day while we are asleep,” he wrote, and yet there “remains only a brief spell of declining daylight in which to spend the short period of leisure at our disposal.” 

For years, Willett lobbied Parliament for legislation mandating the change—then died just a year before it was adopted, when the U.K. followed Germany in making the move to conserve daylight, and thus fuel, during World War I. In 1918, the U.S., which was by then one of the combatants too, got on board with the time change. The clocks returned to their pre-war settings after the fighting ended, only to resume the Daylight Saving Time tradition in the U.S. for the duration of World War II. Finally, in 1966, Congress passed the [Uniform Time Act](https://www.transportation.gov/regulations/time-act), dividing the year into two: six months of Daylight Saving Time and six months of Standard Time. In 2005, lawmakers mandated eight months of Daylight Saving Time.

## Daylight Saving Time is not even effective

But does changing the clocks really conserve fuel? [According to Stanford University](http://large.stanford.edu/courses/2021/ph240/segal2/), one meta-analysis of 44 studies found that it essentially does not, leading to just a 0.34% reduction in electricity consumption. Some research shows it even backfires. A [2008 study](https://www.nber.org/papers/w14429) from the National Bureau of Economic Research found that nationwide, added daylight can actually increase energy consumption by about 1%, due partly to [greater use of air conditioning](https://www.nytimes.com/2018/03/14/climate/daylight-saving-time-electricity.html#:~:text=But%20does%20daylight%20time%20still,more%20air%20conditioning%20and%20heating.) when the sun is out later in the evening.

## It’s lousy for your health

The downsides are even clearer in terms of health. Sleep expert Adam Spira, professor of mental health at Johns Hopkins University in Baltimore, [cites](https://publichealth.jhu.edu/2023/7-things-to-know-about-daylight-saving-time) a range of problems that can occur when we trade an hour of sleep for an extra hour of sun—as we do with Daylight Saving Time—including daylight-induced sleeplessness when bedtime arrives and morning drowsiness when we wake up in the dark. Studies have linked such circadian disruption to an increased risk of [heart attack](https://www.mdpi.com/2077-0383/8/3/404), [stroke](https://www.sciencedirect.com/science/article/abs/pii/S1389945716302222?via%3Dihub), [inflammatory markers](https://www.sciencedirect.com/science/article/abs/pii/S0889159115000069?via%3Dihub), and even [suicide](https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1479-8425.2007.00331.x). Spira also cites a [2020 study](https://www.cell.com/current-biology/fulltext/S0960-9822%2819%2931678-1) which found that moving clocks forward one hour carries an alarming 6% increased risk of fatal traffic accidents, due to similar circadian scrambling and sleep deprivation.


Young children and teens suffer too. Establishing a fixed and predictable sleep cycle for infants and babies can be a challenge, and once things are set, even small disruptions can cause headaches for parents and fitful slumber for babies. A [2019 study](https://academic.oup.com/sleep/article/42/Supplement%5F1/A97/5451230) in the journal _Sleep_ found that springing ahead one hour into Daylight Saving Time leads to broken sleep during the night and earlier awakenings in the morning for babies in the newborn-to-24-month age group. In 2022, [research](https://aasm.org/study-shows-that-teens-lose-sleep-after-change-to-daylight-saving-time/#:~:text=Average%20cumulative%20sleep%20loss%20on,and%20increased%20lapses%20of%20attention.) conducted by the American Academy of Sleep Medicine revealed that teens lose an average of 32 minutes of sleep a night after the switch to Daylight Saving Time—a seemingly small difference that can lead to not-so-small consequences, with increased sleepiness, slower reaction times, lack of attentiveness, and sluggish psychomotor reactions resulting. 

“We’re affected by this not just one day of the year, but really eight months of the year,” says Dr. Beth Malow, professor of neurology and pediatrics and director of the Vanderbilt Sleep Division at Vanderbilt University in Nashville. “We need morning light to reset our clocks. Teenagers are going through puberty and their melatonin levels are delayed, and it just cuts into their sleep when they get too much light too late in the day and not enough light in the morning.”


## No one can agree how to lock the clock

All of this is exasperating to Americans who are broadly in favor of eliminating the practice of changing the clocks twice a year. In a [YouGov poll](https://docs.cdn.yougov.com/etwjvohrxx/Daylight%5FSaving%5FTime%5FToplines%5FCrosstabs.pdf) of 1,000 U.S. adults conducted last year, 62% said that toggling between Daylight Saving Time and Standard Time should be eliminated, with just one fixed time established year-round. Daylight Saving Time actually proved more popular than Standard Time: 56% of respondents said they preferred the extra hour of sunshine at the end of the day and 26% preferred the darker, winter way of doing things. 

State legislatures are trying to respond to this sentiment, with [29 considering laws last year](https://www.ncsl.org/transportation/daylight-saving-time-state-legislation) that would establish permanent Daylight Saving Time, but those efforts are going nowhere. One problem, as [The Hill reports](https://thehill.com/homenews/nexstar%5Fmedia%5Fwire/4282223-daylight-saving-time-lawmakers-tried-to-lock-the-clocks-this-year-what-happened/), is that [federal law](https://www.transportation.gov/regulations/time-act) allows states to establish permanent Standard Time, but not permanent Daylight Saving Time. The rule goes back to 1966, when the Uniform Time Act sought to forestall some states from rushing pell-mell to grab that extra hour of evening sunlight while others resisted. 


To change those rules requires Congressional action. The [Sunshine Protection Act of 2023](https://www.congress.gov/bill/118th-congress/house-bill/1279) is trying to establish permanent Daylight Saving Time and eliminate further time changes after this one. So far, it hasn’t been successful. Some groups, including the American Academy of Sleep Medicine, oppose it—instead favoring permanent standard time. In a January [position statement](https://jcsm.aasm.org/doi/10.5664/jcsm.10898), the American Academy of Sleep Medicine wrote that permanent standard time “aligns best with human circadian biology.” Daylight Saving Time was made permanent in the U.S. once before, in 1974, then [repealed eight months later](https://time.com/6157915/daylight-saving-time-history/) after concerns for children’s safety going to school in the dark.

The one thing everyone seems to agree on, though, is that the clock should not switch twice a year. Not that it’s likely to stop anytime soon.“I think a lot of this is inertia,” says Malow. “People don’t want to change.”

For now, the best Americans can do is resign themselves to the fact that this spring, as in so many springs past, we will be selling an hour in the morning to buy an hour at night—and in the fall we’ll do things the other way all over again.

Daylight Saving Time Is the Worst

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