Clocks stay in daylight saving, but analysis backs permanent standard time

VANCOUVER – Ralph Mistlberger’s light is adjustable, allowing him to have the full spectrum of options depending on what his internal clock needs.

“You want cool in the morning. You want warm in the evening or warm in the afternoon,” he said.

“And so, it goes from being more bluish in the morning to more reddish in the evenings. Both of those are important because artificial light affects your clock.”

Mistlberger knows real sunlight is better than a lamp, but after more than 40 years as a neuroscientist studying sleep and the body’s circadian rhythms, he’s preparing for what’s to come Nov. 1.

That’s when clocks would normally have turned back an hour for most of Western Canada. But they’re staying where they are, putting residents on permanent daylight time.

Mistlberger said it’s a mistake and he and other researchers from British Columbia have released an analysis warning of the potential risks to health, the economy and students’ well-being with the darker mornings on the way.

The analysis by economic, mental health and sleep experts was published Monday in the Canadian Medical Association Journal and examined multiple studies and concluded that health evidence favours moving to permanent standard time — not daylight saving — in part because it better aligns with the body’s rhythm.

Mistlberger, a psychology professor at Simon Fraser University, said people may think they want more sun in the evening, but the impact of starting your winter day in the dark is far-reaching.

“You’re actually waking up at an earlier circadian phase. Your clock may still be telling your brain and your body that this is the sleep period. It’s not time to wake up yet,” he said.

“The same is going to happen in the evening. It’s going to be telling you this is still the wake period, it’s not time to go to bed yet.”

He said not being able to get consistent sleep can lead to what scientists call “social jet lag,” when someone’s life and social calendar doesn’t line up with their biological clock.

Small amounts of sleep deprivation can be reversed with a good, long snooze, he said, but if the issue becomes chronic it can lead to health concerns.

That can include more cases of metabolic disorders, like obesity and diabetes, as well as cardiovascular disease. He said epidemiological studies of large populations have found increases in cancer and some mood disorders.

B.C., Alberta, the Northwest Territories and Manitoba all announced this year that they would adopt permanent year-round daylight time.

The B.C. government pitched that the move would “improve people’s overall health, reduce disruptions for families, simplify scheduling and provide an extra hour of evening light during the winter months.”

It said more than 223,000 people participated in a 2019 online survey and 93 per cent preferred a change to year-round daylight time.

Both Mistlberger and Patrick Baylis, a co-author of the analysis, said the government survey didn’t give the public the option to choose permanent standard time.

“The survey gave two options, which were comparing a switching regime, which is what we have previously had, to permanent daylight time. But those are the only two options. Baylis said.

Baylis, an associate professor at the Vancouver School of Economics at the University of British Columbia, said one of the biggest concerns is what it will mean for students going to school in the dark.

A study of students around the time zone boundary in Florida showed an extra hour of sunlight before school was associated with higher math and reading scores among adolescents. The analysis said it was “comparable in magnitude to meaningful class-size reductions and largest at puberty when circadian rhythms are most sensitive.”

“At minimum we should be thinking about monitoring for some of these negative effects on schooling outcomes, particularly among adolescents,” Baylis said in an interview.

While there is limited economic research, Baylis said some studies suggest exposure to sunlight can affect productivity.

A study that looked at variation in sunset timing within U.S. time zones found that an hour of later sunset reduces earnings over the long run by about five per cent.

Some countries that tried to make the switch to permanent daylight saving have not fared well.

Russia made the move in 2011 but reversed it three years later.

“Public dissatisfaction grew rapidly, particularly in northern regions, where winter morning darkness was even more prolonged, with critics citing disrupted biological rhythms, morning travel risks and effects on daily functioning,” the study said.

Most of Chile’s decision to change in 2015 was also reversed “after complaints about reduced school attendance, scheduling disruption and agricultural effects,” it said.

In 1974, all of the United States adopted permanent daylight saving as an energy-conservation measure.

“The policy was abandoned within the year after widespread opposition to dark winter mornings, concerns about children travelling to school before sunrise, workplace safety concerns and limited evidence of meaningful energy savings,” the analysis said.

The study recommends that choosing to stay with permanent daylight time should include steps to reduce the potential health effects and to evaluate the change.

Baylis said that could mean more flexible or later school start times or helping schools supplement the lack of real light in the morning.

Mistlberger said educating people on the potential impact is important, using bright lights in morning with adjustable bulbs to dim them by the evening.

“You want to get as much light exposure as you can as early as possible in the day when you go outside. So, even though the sunrise is going to be later than usual, it’s going to help you to get outside as soon as there is some sunrise.”

This report by The Canadian Press was first published Oct. 5, 2026.