For anyone whose alarm clock is their phone, turning our clocks ahead for “spring forward” is automatic and not something to add to our to-do list. Unfortunately, though, losing an hour of sleep and dealing with the resulting grogginess still is. For many people, especially those with small children and pets (who live by their routines), daylight saving time — the block of time between mid-March and early November when our clocks are set forward by an hour — can create a huge shift away from comfort, towards stress.
This year, daylight saving time will begin on Sunday, March 10, 2024 at 2 a.m., marking the end of standard time until November 3, 2024, when we "fall back" and set our clocks back again by an hour.
“Time changes affect everyone in different ways,” says Dr. Chris Winter, neurologist, sleep expert, and author of “The Sleep Solution” and "The Rested Child." “Some people feel few effects; others experience greater difficulties.” And those with existing sleep issues? Unfortunately, daylight saving time can make them worse.
With a ringing endorsement like that, it’s no surprise that the practice has a lot of critics, with 63% of Americans saying they would rather observe a fixed, year-round time, according to 2020 poll conducted by the American Academy of Sleep Medicine (AASM).
However, this American dream isn’t coming true anytime soon. Although several senators have introduced the “Sunshine Protection Act of 2018,” which would make daylight saving time permanent throughout the country, the legislation has yet to be passed each year it’s been reintroduced.
The pros? More natural daylight in the late afternoon during warmer months of the year. (More on why this was historically important, below.) The cons? Trying not to lose sleep over getting your body, family, and pets in sync with the time change.
Read on to learn about the history of daylight saving time and how to navigate the health impacts you might encounter this spring.
When is daylight saving in the USA?
Daylight saving in the USA starts on the second Sunday in March at 2 a.m. local standard time. This is known as “spring forward,” or more colloquially as “losing an hour of sleep.”
Daylight saving time ends on the first Sunday in November when we move our clocks back one hour at 2 a.m. local standard time to 1 a.m. local standard time. When we “fall back” we gain an extra hour of sleep.
What are the states that don’t observe daylight saving time?
In the United States, Hawaii and Arizona (save for the Navajo Nation) are the only two states without daylight saving time.
Puerto Rico, the U.S. Virgin Islands, American Samoa, the Northern Mariana Islands, and Guam also observe year-round standard time.
Around the world, approximately 70 countries observe daylight saving time. In Europe, it’s typically practiced between March and October. The largest countries not to practice daylight saving time are China, India, and Japan.
Why did daylight saving time start?
Daylight saving time was created to save money by encouraging energy efficiency. Although the initial idea is often misattributed to Benjamin Franklin, New Zealander George Hudson, an entomologist and astronomer, is believed to have invented daylight saving time in 1895.
Daylight saving time was also championed by William Willett, a British builder, in England 1907, but his proposal wasn’t put into practice until 1916 as a way for countries to reduce reliance on artificial light and help save fuel for their efforts in World War I.
Here’s another fun surprise: It's a myth that daylight saving was created for the farming industry to gain more daylight hours to work in the field. U.S. farmers actually lobbied against daylight saving time in 1919 and have been against it for years.
Although farmers convinced President Woodrow Wilson to repeal daylight saving time, it was reinstated during World War II to save energy resources. Since then, however, research has shown that only 0.34% of modern electricity usage is saved across 77 countries during daylight saving time.
How losing an hour of sleep affects your health and wellbeing
In the spring, when we set our clocks ahead, people lose an average of 15-20 minutes of sleep, according to a study published in the Journal of Economic Behavior & Organization. Many also report reduced sleep quality for up to two weeks afterward, finds a separate study published in Current Biology.
For some, this sleep loss and schedule disruption is an exhausting inconvenience (parents of small children, we’re looking at you). But for others, "spring forward” can pose a greater risk.
In fact, the researchers of a large study published in PLoS Computational Biology estimate that each spring-daylight-saving-time shift is associated with negative health effects: 150,000 incidences in the U.S. and 990,000 globally.
When these researchers crunched the numbers, four prominent risk clusters emerged:
- Cardiovascular diseases: This study found an increase in heart disease rates in men and women over the age of 60, which is in line with prior research on heart attacks and strokes, as well as an approximately 10 percent increase in the risk for some cardiovascular and heart diseases in patients under 20 years of age.
- Accidents and injuries: Prior research links the beginning of daylight saving time to an increase in fatal traffic accidents (up to 30 percent on the day we “spring forward”) and a short-term rise (about 6%) in workplace injuries. This study also noted a rise in accidents and injuries: Children and young adults appeared more prone to accidents resulting in injuries to the head, wrist, and hand, while adults age 41 and older were more likely to injure the area between their neck and lower torso.
- Mental and behavioral disorders: Researchers attribute the elevated risk of mental and behavioral disorders to increased use of psychoactive substances, especially among men age 41 to 60.
- Immune-related diseases: According to the same study above, immune-related disorders tend to become more common than expected in the first week following “spring forward.” For example, noninfective enteritis (inflammation of the small intestine) and colitis (inflammation of the inner lining of the colon) rose 3% in women over age 60 and 6% in boys under age 10.
Experts are still trying to work out exactly why daylight saving time appears to have such a big effect on our health and wellbeing, but sleep loss, disruption to our circadian rhythms, and any resulting stress and drowsiness appear to play a big role.
Even with health events, like heart attacks, which are likely tied to a pre-existing condition (like heart disease), experts say that the stress of daylight saving time may act as a trigger that worsens that pre-existing condition, causing the heart attack.
The problem is big enough that in 2020, the AASM released a position statement in the Journal of Clinical Sleep Medicine in support of observing a fixed standard time, writing “Current evidence best supports the adoption of year-round standard time, which aligns best with human circadian biology and provides distinct benefits for public health and safety.”
How to “spring forward” and still get quality sleep
It may feel dystopian to know you can’t control your digital clocks, but you do have some control over how the time change affects you.
To ease the transition, give the following tips a shot:
1. Adjust your activities. “Start going to bed 15 to 30 minutes before your usual bedtime in the days leading up to the [time] change,” recommends Winter. “Consider moving other activities back in those same increments of 15 to 30 minutes, such as lunch, dinner, and exercise, so that you’ll be used to the time change when it occurs.”
2. Go “dark” earlier. It will be light later in the day once daylight saving time starts, so “put sunglasses on to create an artificial sunset,” suggests Winter. Wearing sunglasses around your house may sound wacky, but it minimizes your nighttime exposure to light, which can help your brain kickstart the production of the sleep hormone melatonin.
3. Find the light. In the mornings, expose yourself to any form of bright light. It can help re-align your circadian rhythm. If you’re up before the sun rises, consider using an alarm clock that gradually lights up, or set an alarm 30 minutes before you need to get up and turn on your room light.
4. Encourage your kids to exercise. Research shows that when kids get more exercise than they usually do during the course of one day, they go to bed earlier, sleep longer, and sleep better that night.
5. Avoid filling up your “sleep tank” in advance. “Taking a two- or three-hour nap before daylight saving time won’t prevent you from feeling the effects. It might, however, mess up your normal sleep routine,” says Winter. If you’re tired after the transition, a 20-minute power nap, early in the afternoon, is a good choice.
6. Limit your caffeine and alcohol intake. Although caffeine is a stimulant and alcohol is primarily a depressant, they can both negatively affect your sleep. Try to avoid both within 4 to 6 hours of bedtime — at least during the first week of daylight saving time.
Armed with this information, you'll be ready for the time change. Planning ahead can help you take on the day, no matter what time it is!
