Study: Lack of morning light keeping teenagers up at night

201002171335 Zoe Caira wears a personal light-measuring device, called a Daysimeter, to monitor her rest and activity patterns and the amount of circadian light -- short-wavelength (blue) light -- reaching her eyes. Credit: Rensselaer Polytechnic Institute

Rensselaer Polytechnic Institute recently conducted a field study to learn the effects of morning light on teenagers' sleep cycles. They concluded that a lack of exposure to early morning light can result in a 30-minute delay in the onset of sleep.

"If you remove blue light in the morning, it delays the onset of melatonin, the hormone that indicates to the body when it's nighttime," explains Dr. Figueiro. "Our study shows melatonin onset was delayed by about 6 minutes each day the teens were restricted from blue light. Sleep onset typically occurs about 2 hours after melatonin onset."

The study findings should have significant implications for school design. "Delivering daylight in schools may be a simple, non-pharmacological treatment for students to help them increase sleep duration," concludes Dr. Figueiro.

The new research has applications for more than 3 million shift workers and Alzheimer's patients who suffer from lack of a regular sleep pattern.

Studies have shown that this lack of synchronization between a shift worker's rest and activity and light/dark patterns leads to a much higher risk of cardiovascular disease, diabetes, seasonal depression and cancer over decades.

Lack of morning light keeping teenagers up at night


  1. personally, i find a sleep schedule of 5-6 hours on work nights and a humongous catch up on saturday (14 hours) is what works best for me.

    then again, i’ve been known to sleep for well over 24 hours on occasion. i went balls out ay my first burningman and ended up missing all of wednesday, a full 22 hour recovery. if i weren’t employed, i might be biologically inclined to put the conscious state in the minority of possible modes of existence.

    also, being horribly addicted to cigarettes, it’s the only time i can go long stretches without one. i’ve heard of smokers who will wake up with cravings if they sleep too long, but i aint one of em. when i take the final plunge into quitting, i imagine it’ll have to start with a nice long sleep.

  2. Growing up in Alaska, everyone’s sleep patterns shifted with the seasons… During the summer you could only get a few hours of sleep per night, and it wouldn’t really affect your energy level for the rest of the day, whereas you really couldn’t help but hibernate thru the winter.

  3. This isn’t the first finding of this timing effect of blue light frequencies. There is a special melanopsin receptor in the periphery of the retina that responds to blue light frequencies (daylight) and reduces melatonin production, setting the circadian rhythm. Along with getting blue light frequencies in the morning, another important step to improving sleep is to limit such frequencies later in the day. Fluorescent lights, TV and computer monitors all tend to cast more blue frequencies. If you install and use “bug-lights”– yellow incandescent or fluorescent bulbs– or wear orange/blue-blocking goggles like the woman in the picture, and use them for a few hours before sleeping, you may find it much easier to change sleep behavior and get to bed earlier. The goggles are especially useful if you do want to look at a screen before bed.

  4. Interesting idea about more daylight in schools. Not practical though.

    Despite the propaganda stories of rampant waste and millionaire teachers, schools have no money to buy big watt full spectrum lights let alone pay a higher electricity bill. The lack of spare cash and the inability to get levies passed explains why many schools built over the last decade or two lack the kind of windows we Boomers used to gaze out of in history class.

    Maybe the lack of light is why vampires are so popular with teens.

  5. why not just suggest that students put a light on a timer by their bedside in the morning to help wake them up? it works for me!
    p.s. I lived in Alaska, too, and had no problem sleeping through the midnight sun (‘though waking up from a midafternoon nap was often disorienting and I’d have to figure out which side of the sky the sun was on to determine if I was supposed to go to breakfast or dinner)

  6. I have had insomnia for years, and one of the methods my doctor tried was to make me sit under a high-powered LED light for a half hour every morning, to simulate sunlight. The idea was to reset my circadian rhythm. It worked, but only for a month or so, and only if I sat under it every single day at the same time. My circadian rhythm disappeared almost immediately if I stopped using the light, even for a day or two. Eventually it stopped working even if I sat under it regularly. Sleep is complicated stuff, and it’s different for everybody.

  7. When I was in high school and particularly in college, the work kept me up. Going to sleep was never the issue, getting everything in a day done was the problem. But maybe that was just me, but I don’t imagine it has gotten any better in a decade or so…

  8. I’m a physician, and I routinely educate my patients on sleep hygiene. I wrote a two-page handout and one of the first things on it is the recommendation to get sunlight on the face early in the morning. I think this is especially important for older folks whose circadian rhythms tend to be weak.

  9. I’ve always selected houses/apartments based on morning light. If the bedroom doesn’t have east-facing windows, I don’t even bother to check it out. My first apartment was a very, very small studio that I shared with a friend. My bed was out on the balcony (which was only slightly larger than my twin bed) facing east. That turned me into someone quite happily addicted to morning sunlight.

  10. the goggles they do nothing! i’m fully aware how important sunlight is, the best thing is to find out what works best for you and stick to it – even if that means several bulbs on separate timer switches :D

  11. Allergic to sunlight, I removed the morning from schedule, wake up before dawn, go out to and off work ( where the workspace is FULL blinds ON), when the sun sets, for over 20 years have not missed it or have any described symptoms whatsoever.
    If I have to go trough daylight, I go inside fast.
    Not missing it for a second.

    I’m also pale as this page, and have anemia, blond and blue eyed, so the sun and light in general makes me either dizzy, tearful or causes burns, and acute headaches.

    It really helps being in the IT industry, to maintain this kind of schedule and environment for oneself.

    Though I’ve been told the lack of sunlight is bad for bones and skin in general, I’ve seen only improvemnt over burns and redding.

    But a good study all together.

    All I can reccomend to sun lovers is never to go outside without adequate skin protection especially from 1000 – 1600 H.

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