How you protect your heart (and health) heading into Daylight Saving Time

You might be dreading putting your clock ahead this Sunday and plenty of research shows it's not without good reason. Several studies have found springing ahead comes with a slew of negative consequences, including decreased productivity and a spike in traffic accidents.

When our bodies are no longer in sync with the environment, 'it's hazardous to our health,' researcher says

Daylight saving time starts on Sunday, but some research shows it may be time to end the practice of springing ahead for the good of our health. (Pixabay)

You're probably already dreading putting your clock ahead when daylight saving time starts this Sunday and plenty of research shows that's not without good reason.

Several studies have found springing ahead comes with a slew of negative consequences, including decreased productivity and a spike in traffic accidents.

A 2014 study out of the University of Colorado found a 25 per cent increase in the risk for heart attacks the Monday after daylight saving time starts.

It also noted a corresponding decrease in the risk for heart attacks at the end of daylight saving time in the fall.

Dr. Tami Martino, director of the Centre for Cardiovascular Investigations at the University of Guelph, said there can be negative effects anytime our bodies become out of sync with the environment.

That's because the circadian clock, the 24-hour cycle that's encoded in our DNA, is a fundamental part of our health.

The daily cycle

"Essentially every single cell in our body is connecting with just light. It's connecting our bodies to the outside universe, to the sun and the sky, and sort of syncing us with the environment," Martino said.

"Studies by our group and lots of others show that when that happens — we call that circadian dyssynchrony — or when we get light at the wrong time, it's hazardous to our health."

Everything from cortisol levels to blood sugar and metabolism is tied to the cycle of light and dark, Martino said.

Her research has also found patients recovering from heart attacks heal better when their day-night cycles aren't interrupted.

It's easy for the body to get out of sync, though.

"Maintaining normal sleep and circadian rhythms, not being on your phones, not getting the blue light from your computers at night would be one thing that would keep your body a little bit in sync in the first place, even before you add this added effect of daylight saving time on top," she said.​

No more changing clocks?

The growing body of research on this issue has prompted places around the world to reconsider daylight saving time.

The European Commission put forward a proposal in 2018 to end the practice, and a private member's bill to eliminate daylight saving time in November 2019 is currently before the Manitoba legislature.

There are already some places in Canada that won't be setting their clocks ahead this Sunday. Saskatchewan is currently the only province where all municipalities don't observe daylight saving time.

In Ontario, there are three towns where the clocks stay the same year round.

Dennis Brown, the mayor on Atikokan, said there have been multiple attempts to get the northwestern Ontario township to adopt daylight saving time. So far, they haven't stuck.

"I know it's not perfect, because it does cause some confusion, you know for patient care at the hospital, administrative problems with outside visitors and that kind of thing," he said.

"But people, you know, the majority want it to stay the way it is."


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