Sleep Apnea Updated November 2, 2023 6 min read By Nick Zacharias

Get the lowdown on Daylight Saving Time

A clock being turned back an hour for the fall Daylight Saving Time change

This weekend will bring a treat to those who love to sleep. Daylight Saving Time kicks in early Sunday, Nov. 5th, meaning you’ll need to set your clocks back an hour on Saturday night.

Of course, talking about DST brings up the inevitable debate about the usefulness of the practice. The biggest consequence: The change shifts daylight back into the morning hours. For 9-to-5 office workers, it means saying goodbye to leaving work while it’s still light out. And for weekend workers, it means an additional glorious hour of sleep on Sunday. Hurrah!

Yet there’s still a lot of confusion about daylight saving time. The first thing to know: Yes, it ends in the fall, just as the decrease in daylight hours is becoming noticeable. But, why do we deprive ourselves of sunlight in the winter when we need it most! Get the lowdown on Daylight Saving Time here.

Key takeaways

  • DST started as a 1908 energy-conservation trick, but the actual electricity savings are unclear — energy-wise, it’s “a wash.”
  • It’s “daylight saving time,” singular — not “savings.”
  • Most of Saskatchewan never changes its clocks, effectively observing DST year round.
  • Lost sleep at the spring change is linked to more fatal crashes, workplace injuries and heart attacks — a real risk if you have sleep apnea.

Why do we need to “save” daylight hours in the summer?

Daylight saving time in Canada started as an energy conservation trick in 1908, and expanded through World War I to become a (mostly) national standard in the 1960s to keep in step with the US. The idea is that in the summer months, we shift the number of daylight hours we get into the evening. So if the sun sets at 8 pm instead of 7 pm, we’d presumably spend less time with the lights on in our homes at night, saving electricity.

Isn’t it “daylight savings time” not “daylight saving time”?

No, it’s definitely called “daylight saving time.” Not plural. Be sure to point out this common mistake to friends and acquaintances. You’ll be really popular.

Does it actually lead to energy savings?

As Joseph Stromberg outlined in an excellent 2015 Vox article, the actual electricity conservation from the time change is unclear or nonexistent:

“Despite the fact that daylight saving time was introduced to save fuel, there isn’t strong evidence that the current system actually reduces energy use — or that making it year-round would do so, either. Studies that evaluate the energy impact of DST are mixed. It seems to reduce lighting use (and thus electricity consumption) slightly but may increase heating and AC use, as well as gas consumption. It’s probably fair to say that energy-wise, it’s a wash.”1

— Joseph Stromberg, Vox (2015)

What does Saskatchewan know that we don’t?

Although all of Saskatchewan is geographically within the Mountain Time Zone, the province is officially part of the Central Time Zone. Most of Saskatchewan never changes their clocks, in fact they technically observe DST year round.2 The odd result is that their clocks match Winnipeg during the winter, and Calgary and Edmonton in summer. Though that seems funny, with the energy benefits being questionable, and all of the very real headaches that come from the semi-annual shift, no wonder our friends in Saskatchewan can get a little smug about opting out of the madness.

Is daylight saving time dangerous?

When we shift clocks forward an hour in the spring, many of us will lose that hour of sleep. In the days after daylight saving time starts, our biological clocks are a bit off. It’s like North America has been given an hour of jet lag. One hour of lost sleep sounds like a small change, but if you suffer from Obstructive Sleep Apnea, you know what sleep disruptions can do to your alertness and your overall health.

According to Stuart Fogel, an assistant professor of psychology at the University of Ottawa, it’s in the second half of the night that you switch to rapid eye movement (REM) sleep, which is associated with dreaming. During this time you have spikes in brain activity that are important for learning and memory, as well as for mood regulation and cognitive function.3 Chopping an hour from that stage of sleep will obviously have consequences for those processes, so it’s no wonder we all feel groggy after the clocks “spring forward” every March.

The practical fallout is real. In 1999, researchers at Johns Hopkins and Stanford universities wanted to find out what happens on the road when millions of drivers have their sleep disrupted. Analyzing 21 years of fatal car crash data from the US National Highway Transportation Safety Administration, they found an increase in road deaths on the Monday after the clock shift in the spring: the number of deadly accidents jumped to an average of 83.5 on the “spring forward” Monday compared with an average of 78.2 on a typical Monday.

83.5
avg. deadly crashes on the “spring forward” Monday
78.2
avg. deadly crashes on a typical Monday
21 yrs
of fatal-crash data analyzed

And it’s not just car accidents. Evidence has also mounted of an increase in incidences of workplace injuries and heart attacks in the days after we spring forward.

Can’t we just get rid of Daylight Saving Time?

If only it were that easy! British Columbia is tabling new legislation this fall proposing to keep B.C.’s clocks fixed all year, a move supported by 93% of the province.4 The trouble is that economically it makes much more sense for them to stay in step with states like Washington and California, who have also considered the move, but who can do nothing without congressional approval from D.C. It means that wherever you are in Canada, it doesn’t seem likely that change will come unless we decide to live with time zones that differ from our friends south of the border.

So what should I do about it?

Well, for the fall, you should take your extra hour of sleep and enjoy it! Then come next spring, when you have to pay it back, make sure to get in lots of activity the day before, and consider using an over the counter herbal sleep aid to help you get to bed earlier on the day of the change. And as always, remember to consult the sleep experts at Apnée Santé for more tips and help with getting a great night’s sleep.

Talk to a sleep expert

Struggling with the time change?

If lost sleep leaves you groggy and you suspect sleep apnea, find out with a simple home sleep test.

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Frequently asked questions

Is it “daylight saving time” or “daylight savings time”?

It’s definitely called “daylight saving time” — not plural. It’s a common mistake worth pointing out to friends.

Does daylight saving time actually save energy?

The evidence is mixed. DST seems to reduce lighting use slightly but may increase heating, AC and gas consumption. As a 2015 Vox article put it, energy-wise it’s probably “a wash.”

Why doesn’t Saskatchewan change its clocks?

Although geographically in the Mountain Time Zone, Saskatchewan is officially in the Central Time Zone and most of it never changes its clocks — effectively observing DST year round. Its clocks match Winnipeg in winter and Calgary and Edmonton in summer.

Is the time change dangerous?

Losing an hour of sleep in spring throws off your biological clock, like an hour of jet lag. A 1999 analysis of 21 years of fatal crash data found deadly accidents rose to an average of 83.5 on the “spring forward” Monday versus 78.2 on a typical Monday, and workplace injuries and heart attacks also rise. The effect is especially serious for people with obstructive sleep apnea.

What can I do to handle the change better?

For the fall, enjoy your extra hour of sleep. Come spring, get in lots of activity the day before and consider an over-the-counter herbal sleep aid to get to bed earlier on the day of the change. And consult the sleep experts at Apnée Santé for more help getting a great night’s sleep.

Apnée Santé provides this online information for education and communication purposes only and it should not be construed as personal medical advice. Information published here is not intended to replace a consultation with a physician regarding your medical care.