Oct. 6, 2021

Circadian rhythm expert cautions Albertans against permanent daylight savings time

Oct. 18 referendum neglects permanent standard time, the right option for public health, says UCalgary psychologist
map showing different time zones
Graphic by Michael Antle

As a renowned expert on the brain’s circadian clock, which regulates sleep/wake rhythms, Dr. Michael Antle, PhD, has long argued against the twice-a-year “spring forward / fall back again” time change that Albertans live by.

It might come as a surprise, then, that the University of Calgary professor in the Department of Psychology is highly critical of the referendum vote on the time change, which is being posed in the Alberta Municipal Election on Oct. 18, with advance voting underway this week.

The referendum question, which allows for a yes or no vote, asks: “Do you want Alberta to adopt a year-round daylight savings time (DST), which is summer hours, eliminating the need to change our clocks twice a year?”

  • Image above: When our clocks and the sun are aligned, the sun is at its zenith at 12 noon. To highlight how offset Alberta will be on DST (Universal Coordinated Time (UTC)-6), when our clocks read 12 p.m., the sun will be at its zenith over Thunder Bay, Ont., 2,000 kilometres east of Alberta.

Despite his scientific evidence-based aversion to the time change, Antle is also opposed to the introduction of permanent DST, which, he asserts, comes with even greater negative consequences for public health. Crucially missing in the referendum vote, Antle notes, is the option for a move to permanent standard time.

“Albertans are being given a bad choice and a worse choice,” says Antle, who is also a member of the Hotchkiss Brain Institute at the Cumming School of Medicine and an adjunct professor with the Department of Physiology and Pharmacology.

Michael Antle

Michael Antle.

Riley Brandt, University of Calgary

“Permanent DST is a move to summer hours, and everybody loves summer, right? A vote against summer just seems mean. People think that following Daylight or Standard time in the winter is an arbitrary choice without consequences, that it’s simply a matter of 'pick what you like.' In fact, there are tremendous negative consequences if we move to permanent DST.”

That’s because DST delays the dawn and our circadian clocks depend on morning light to be in proper alignment, explains Antle, who is weighing in on the matter as vice-president of the Canadian Society for Chronobiology. Antle notes that in the early 1970s the United States adopted a year-round DST which they quickly abandoned, due in a large part to an increase in car accidents during the winter months.

Car accidents, strokes, heart attacks, workplace injuries

“It’s hard enough to wake up in the winter when our sunrise comes much later,” says Antle. “Especially in Alberta where we’re so far north. We wind up forcing ourselves out of bed and behind the wheel of a car well before our bodies are ready. And that’s what causes the accidents — sleepy drivers. Studies have shown that getting behind the wheel when you’re sleepy can be just as bad as getting behind the wheel when you’re intoxicated.”

Antle also disputes the twice-a-year time change because the weeks following the “spring forward” in April, when we switch our clocks ahead by an hour, see an increase in car accidents, strokes, heart attacks and workplace injuries. However, he asserts that the proposed move to permanent DST is the worse of the two dreadful choices.

“That move will give us five bad months when we’re forcing ourselves to wake up long before our bodies are ready,” he says. “Our circadian clock always follows the sun, and our sunrise comes so late when we’re in Daylight time. Meanwhile, our bosses and teachers demand that we follow the clocks on our wall, or on our phones, and our circadian clock struggles to do that. It leads to something we call social jet lag, and it poses very real threats to our health.”

Later morning light 

Antle points out that Albertans, who live in the Mountain Standard Time Zone, would be especially impacted by the permanent DST move. Our exposure to daylight fluctuates within time zones, depending on where one is geographically located within their zones. The further west we are within our time zones makes for later morning light.

That means in Calgary our sunrise in December won’t come until after 9:30 in the morning. Edmonton’s sunrise will be even later, and Grande Prairie won’t see the light of dawn until almost 10:30 a.m.

Antle notes that before 1972, when it introduced the time changes, Alberta was on year-round standard time. “It’s worrisome that the Alberta government is not even considering standard time as an option now.”

Led by the Hotchkiss Brain Institute, Brain and Mental Health is one of six research strategies guiding the University of Calgary in its Eyes High strategic direction. The strategy provides a unifying direction for brain and mental health research at the university and positions researchers to unlock new discoveries and treatments for brain health in our community.