ScienceDaily: Trouble falling asleep at night? Chase that daytime light, study shows

"Light during the day -- especially in the morning -- advances your clock, so you get tired earlier in the evening, but light exposure late in the day or early night will delay your clock, pushing back the time that you will feel tired," said de la Iglesia. "Ultimately, the time that you fall asleep is a result of the push and pull between these opposite effects of light exposure at different times of the day." Data showed that daytime light exposure had a greater impact than evening light exposure in the UW study. Each hour of daytime light "moved up" the students' circadian phases by 30 minutes. Even outdoor light exposure on cloudy or overcast winter days in Seattle had this effect, since that light is still significantly brighter than artificial indoor lighting, said de la Iglesia. Each hour of evening light -- light from indoor sources like lamps and computer screens -- delayed circadian phases by an average of 15 minutes.

"It's that push-and-pull effect," said de la Iglesia. "And what we found here is that since students weren't getting enough daytime light exposure in the winter, their circadian clocks were delayed compared to summer."

The study offers lessons not just for college students.

"Many of us live in cities and towns with lots of artificial light and lifestyles that keep us indoors during the day," said de la Iglesia. "What this study shows is that we need to get out -- even for a little while and especially in the morning -- to get that natural light exposure. In the evening, minimize screen time and artificial lighting to help us fall asleep."

Some Insights From This Article

• Tired in the evening? Our circadian rhythm may be contributing to some daytime somnolence (sleepiness) even when we are able to get a solid 8 hours daily. Research showed that sometimes staying indoors during the day can contribute to feelings of sleepiness.

• Natural light exposure has a quality of its own to be able to regulate our circadian rhythms normally and allow us to feel less tired throughout the day. Additionally, cutting use of artificial light during the night can also help our bodies fall asleep faster.

What’s something that helps you wake up?

Full article is here!

#Sleep #Nocturnal #Light