How smartphones and tablets affect your sleep

How smartphones and tablets affect your sleep
Are you a smartphone owner and having trouble catching those ZZZZZs at night? You might have to blame the lack of sleep on your handset or tablet. According to the Rensselaer Polytechnic Institute in New York, exposure to the light from a tablet could drop the body's melatonin levels by 23%. For those who ironically slept through high school, melatonin is a naturally occurring substance in the human body that helps a person get to sleep by telling the body when it is dark and time for rest. The institute studied 13 volunteers aged 20 to see how a tablet placed by the bedside affected sleeping habits.

According to the Emory sleep disorders laboratory, you should refrain from using your tablet or phone before bedtime because the light from the tablet shines directly into your eyes. Even the famous Mayo Clinic got into the act last week by suggesting that tablet and phone users turn the light down on their slates before bedtime. The Clinic said that devices emitting more than 30 lux in light can affect melatonin levels in the body.

The Mayo Clinic suggests that you will be alright if you hold your smartphone or tablet 14 inches or more away from your eyes, even at maximum brightness. At that distance, only the Apple iPhone 3G had a reading of 30 lux. If you lower the brightness level, you should be able to bring the phone to your face. Doing that, the Apple iPhone 4 measured only 8 lux, making it safe for insomniacs to look at.

If you're having trouble getting a restful sleep, your best bet is probably to turn off the phone and the tablet and close your eyes. 40% of adults who are awoken by their smartphone just end up using it. Unless you're expecting a call, perhaps you can shut down your phone or at least turn off the volume. If you have an Android flavored phone, TeXT can send out a alarm if someone you know needs you in case of an emergency.

source: GuardianU.K.



1. apple4never

Posts: 1064; Member since: May 08, 2013

hmm never thought this actually made a difference

2. mio15

Posts: 38; Member since: Mar 21, 2011

Interesting. Heard a study/report about this some months before. but what about TV/PC Monitors/Screens? Inflict AMOLED screens the same "damage" as LCD / IPS. Would be interesting to see a bit more about the "techy" side of this study. greets

3. dsDoan

Posts: 235; Member since: Dec 28, 2011

Setting quiet hours on an Android devices will prevent notification sound, while still allowing calls to go through in case of emergencies. I would assume iOS has something similar

4. Fuego84

Posts: 357; Member since: May 13, 2012

I work night shift and occasionally fall asleep holding my phone. I wake when I drop it though.

5. alltechinside

Posts: 248; Member since: Apr 21, 2013

I use twilight (no, not the movie) app to help make my eyes feel better at night. I basically colores the screen red. You might not see a difference at first but you notice it if you try switching back to normal.

6. InspectorGadget80 unregistered

I really don't spend lot of time on my phone that is If I'm doing LOTS OF DOWNLOADING media. I also watch my movies on my Xperia phone during lunch time and breaks unless I"m not on my PC but not very addicted too it. But here's a weird thing. When I have my phone turn on with its alarm i get weird dreams. when I don't have my phone on i don't. doesn't that sounds kinda weird?

7. mr.techdude

Posts: 571; Member since: Nov 19, 2012

LCD displays such as the HTC one x are more brighter and emit more light even though its on the lowest brightness its still very bad to look at it when ur in a dark room, causing strain on your eyes resulting in ur retina forcefully focus too much on the screen. On the other hand, a amoled display such as the galaxy s3 are not bright tend more on a darker side giving the advantage to lcd displays in outdoor sunlight visibility, but in a dark room samoled is ur best bet in a dark room but still bad for your eyes but not as bad as LCD displays. My solution for LCD displays is too download night mode keeping the light emitted to stay inside a layer of dark filter. Sorry for the essay guys :)

8. Taters

Posts: 6474; Member since: Jan 28, 2013

Get some amber goggles or sunglasses for night. It blocks the blue light and keeps your circadian rhythm from being affected by the light. Basically looking at a bright screen emulates sunlight so your body still thinks it is daytime and you get screwed over.

Latest Stories

This copy is for your personal, non-commercial use only. You can order presentation-ready copies for distribution to your colleagues, clients or customers at or use the Reprints & Permissions tool that appears at the bottom of each web page. Visit for samples and additional information.