Researchers have found that exposure to natural light up anytime up to noon has a positive effect on your sleep patterns
A new study has found that exposing yourself to natural light early in the morning may improve sleep quality later that night. Prof Annie Curtis is a circadian biologist at the Royal College of Surgeons and a Research Irelandawardee and she joined the Drivetime team on RTÉ Radio 1 to discuss the results. (This piece includes excerpts from the conversation which have been edited for length and clarity – you can hear the discussion in full below).
Curtis explained that the authors of the report were trying to understand the link between your daylight exposure to sunlight and your sleep. “We know that sleep is really important for pretty much every type of health we have and we are not getting enough sleep. A third of us are getting less than six hours of sleep, and then many of us as well are just not getting sufficient sleep, so we’re not feeling rested.
“What they did was looked at 100 adults for 70 days and asked these individuals to report when they were exposed to natural light and what type of sleep they had that evening. Basically, they were asked to say whether they had the outdoor light exposure in the morning, middle of the day or the evening.
“What’s really interesting is it’s the actual timing of the light. It’s morning light so light anywhere up until about midday is actually more important than how long you’re out in the daylight. It showed it was better for sleep, a thing called sleep latency, which is basically long it takes to fall asleep.”
This will come as a bit of surprise to many, says Curtis. “A lot of us would’ve thought that two hours maybe in the afternoon is better than maybe 30 minutes in the morning, but that’s not the case. It’s all down to our body clocks really, because our body clocks know what time of day it is. They really want to get that morning light and make all the changes in the body to ensure that we get good quality sleep that night.”
We’re almost like a different species from morning to evening because of our body clock
The research also shows that our body can differentiate between different kinds of light. “We get this beautiful kind of orange light in the evenings in Ireland so the spectrum and wavelengths are different in the evening than they are in the morning.
“That spectrum of light is different in the morning, but our bodies are also different in the morning. We’re almost like a different species from morning to evening because of our body clock. Our body clock is actually changing the proteins that are there in the morning versus the evening and in the morning. That’s when it really wants to see that light and make the changes that it does in our body.”
