What Is Blue Light And Why Is It Negatively Affecting Your Good Night’s Sleep? 

Our ancestors used to rely on the sun on lighting and mostly spent their evenings in darkness.  Modern age brings about the discovery of artificial light that provides us with better lighting especially during the night.   

Source: flickr.com


You come home from a long busy day, you lay on your bed, read from your Kindle e-reader or watch TV, and even check emails on your tablet.  We have benefitted so much from lights for illuminating our dark nights and make our lives much more comfortable.  But scientists have warned us regarding the exposure to blue light especially at night, not just those emitted by our electronic devices but also the energy-efficient lightbulbs we use in our homes.   

 Circadian rhythms are regulated by light and darkness and are closely related to our sleep-wake cycles. Sensing natural light through your retina signals the brain to be awake and alert. — Megan MacCutcheon, LPC

Our Circadian Rhythm  

Humans are inherently diurnal in which we are active in the daytime and are supposed to rest or sleep at night.  Each person may have their own routine, yet most of us are still more accustomed to sleeping when it’s dark.    


Circadian rhythms impact our sleep and wake cycle, the release of hormones, eating habits, body temperature, and generally all vital body functions as they are influenced by cues such as daylight (sunrise), noon, and sunset which are considered as nature’s clock.   


Light is essential in regulating our circadian time.  People who experience jet lag spend time outdoors to experience the natural light to allow their bodies to get used to the new time zone.  Exposure to light dramatically affects our sleep.    


The body’s circadian rhythm rules over not just the sleep pattern but also impacts functions of our body organs including cell regeneration, brain activity, and appetite.   

Exposure to artificial light at night is recognized as a hazard to sleep, contributing to rising rates of disrupted and disordered sleep. Different wavelengths of light have been shown to affect human physiology and sleep cycles in different ways. — Michael J Breus Ph.D.

Blue Light Effect On the Circadian Rhythm  

Source: en.wikipedia.org


As mentioned earlier, light has a powerful effect on resetting our circadian clock.  It can interrupt our regular sleep patterns.   When the light reaches our retina, it sends signals to our hypothalamus which is the area of the brain involved in the switch between wakefulness and sleep.  When it gets darker outside, the hypothalamus then sends the signal to the body to start producing sleep hormones, such as melatonin, and to reduce body temperature to prepare the body to sleep.  Once the retina senses the light again, it will tell the body to warm up and produce hormones, such as cortisol, to awaken the body.   


The circadian rhythm becomes confused because of the artificial light that the human body is exposed to.   The body now does not know when to get ready for sleep. 


According to research, the blue light produced by our gadgets and other electronic devices promotes reaction times, mood, and attention which are helpful for the body during the daytime when we need to be alert.   But when we expose our body to the blue light at night, it can cause a problem.   


Researchers also found out that blue light suppresses the creation of melatonin compared to other types of light.  Blue light shorter wavelengths subdue the delta brainwaves, which are responsible for inducing our sleep and boosting alpha wavelengths which produce alertness.  Our body is more sensitive to blue light.   

 Common problems include fatigue, negative mood, problems with work, decreased quality of life, increased irritability, mood disturbance, decreased functioning and increased risk of depression. — John Cline Ph.D.

Suggestions To Reduce Negative Blue Light Effect In Our Sleep 

There’s no better way to reduce blue light affecting your sleep than to limit or avoid using your gadgets 30 minutes to an hour before you go to bed.  But lowering the brightness of your device or making use of filters and wearing blue-blocking glasses (yellow lenses that filter out blue light) can help those who cannot turn off their gadgets due to work.   


Try creating a dimly lit environment (preferably use of dim red light) to assist your body in enhancing melatonin production.  A naturopathic physician also suggests that changing all overhead lights to full-spectrum can help induce sleep.    

Source: pxhere.com


It is best to go out in the sun during the day.  Allowing your brain to determine the difference between a well-lit day and dark night will condition your body when it is time to sleep as well as promote mood and alertness during daylight.   


Getting good quality of sleep is necessary to maintain proper health and alertness.  Light plays a significant role in keeping our body alert and so does darkness which signals our brain that it is time to sleep.  That can be possible when the body starts releasing melatonin a few hours before bedtime.   


Blue light holds back the body’s capability to produce more melatonin which is the hormone that is supposed to put us to sleep.   As we expose ourselves to blue light from our gadgets hours before our bedtime, it delays the melatonin production negatively affecting us from getting a good night’s sleep.    


Using your gadgets while in bed, you expose not only yourself to the blue light but your bed partner, too, making him unable to sleep as well.  To prevent this from happening, either limit the blue light exposure or entirely avoid the use of gadgets and other blue light-emitting electronic devices before your bedtime.  If you could not avoid using your gadget, it would be better to do it in a separate room, or anywhere else but not on your bed or use filter programs to lessen the blue light your device emits.   That will give you and your bed partner a good night’s sleep.