If you have trouble falling asleep at the end of the day, you might want to try this simple trick: wear sunglasses at night.
You don't have to take Corey Hart's word for it. According to sleep researcher Glenn Landry, too much light exposure at night can interfere with the body's circadian clock.
"We have artificial sources of light available to us 24 hours a day," said Landry, who studies sleep as a postdoctoral research fellow at UBC's Aging, Mobility, and Cognitive Neuroscience Lab.
"We've got our laptops with us, and we're doing email and we're watching TV late at night. And so we're getting light at night [which] impacts our circadian rhythms, our daily biological rhythms."
And Landry does more than just talk the talk.
"Beginning at eight at night, two hours before [the] time I want to go to bed, I wear sunglasses. Not because my future's so bright, but because I'm trying to avoid light. I'm trying to tell my clock that this is the end of the day," he said.
Avoiding light at night is only half of the battle. People who don't get enough light exposure during the day are also missing out on important cues to the brain.
"And the long-term impact of that hasn't really been evaluated," said Landry. "But it can't be good for us and it's probably leading to increased circadian dysregulation."
Important for seniors
Teresa Liu-Ambrose is the Canada research chair in physical activity, mobility, and cognitive neuroscience at UBC, and oversees Landry's research. She says monitoring the circadian clock is increasingly important as people age.
"In your 20s you might have gotten away with it. When you're older ... you have to be a little more diligent about providing that stimuli at the most appropriate time," she said.
Liu-Ambrose and Landry are trying to improve sleep quality in seniors. There is a link between poor sleep and dementia, so they hope that by helping seniors protect their sleep, they can slow down age-related cognitive decline.
"Sleep has a lot of potential for preserving brain health across the lifespan," says Liu-Ambrose. "Slowly, but surely, we're all recognizing it."
Liu-Ambrose doesn't go as far as wearing sunglasses to bed, but she has made some changes.
"I'm definitely not as fastidious as [Landry]," says Liu-Ambrose. "But I have definitely started to not work as late."