Random Thoughts

Blue Light’s Dark Side: The Dangers of Staring at a Computer Screen



We bounce from our phones to the navigation screens in our vehicles, to the computers at work, to the television at home, and finally back to our tablets or phones at night; I am not innocent when it comes to this, however, do we ever stop and think about how this affects our health?

Since it is winter and I am longing for that energy-boosting sunshine, I began to notice how often I am staring at a computer screen. I wake up to the alarm on my phone (first thing I see every morning), check how the traffic is on my commute, and then spend 8-hours at work staring at yet another screen. When my shift is complete, what do I do? Either go to the gym (while still looking at a screen to play music) or relax on the couch and watch Netflix. Monitors and displays indeed surround us. Due to these realizations, I decided to do some research on blue light’s effects on the human body.

What is Blue Light?

Blue light is low energy light that we see in the daytime, basically telling our bodies it’s time to be awake; it is also emitted from our electronic devices (television, cell phones, computers, tablets, etc.) Sunlight contains multiple colors and shades, and collectively, they create ‘white light.’ For example, red rays have longer spectrums and less energy; blue rays, on the other hand, have shorter wavelengths and thus contain more energy.

Blue light is what causes eye strain when we abuse the privilege of continually having technology in our hands; this being said, blue light is everywhere; emitted from the sun, LED lighting, and our flat-screen televisions. It is the logical conclusion of many that we should not be staring at this blue light which keeps us awake as we are trying to fall asleep; but what are the side effects?

Side Effects

Macular Degeneration: Our eyes do a poor job at blocking blue light, unlike how they block UV rays. By easily penetrating through the retina, blue light damages light-sensitive cells, causing permanent vision loss.

Eye Strain: Since blue light is more like ‘eye noise’ and can’t be easily focused, it strains our eyes more than any other type of light.

Daytime Fatigue: If you are cuddling your phone or watching shows on the flat screen right before bed, this will disrupt your body’s ability to fall asleep quickly, it’s REM (Rapid Eye Movement) cycle, the circadian rhythm which affects your metabolism, and finally, will affect your overall alertness during the daytime and your ability to function correctly.

Diabetes/Obesity: While it might seem like a reach, blue light can potentially increase the risk of diabetes and obesity. Per a Harvard Study, “researchers put 10 people on a schedule that gradually shifted the timing of their circadian rhythms. Their blood sugar levels increased, throwing them into a prediabetic state, and levels of leptin, a hormone that leaves people feeling full after a meal, went down” (Harvard, 2018).


  • Reduce or eliminate the use of electronics that emit blue light before bedtime (many smartphones, tablets, and other monitors have a blue light filter you can enable)
  • Using a yellow or orange tint in your electronic screens to reduce strain on the retina (there are many apps you can download to achieve this)
  • Take breaks from the screens (not just your computer)
  • Equip yourself with eye gear: doctors are going as far as to prescribe special blue light reducing protective eyewear that is designed to prevent eye strain, among other adverse reactions to prolonged exposure, by merely filtering blue light
  • For night lights, use dim red lights
  • Exposure to blue light during the day is normal, but limit exposure for 2-3 hours before bed

 Benefits of Blue Light

While it is true that too much blue light can be harmful, there are advantages of it as well.

  • High-energy visible light boosts alertness, cognitive function, and helps memory
  • Used to treat SAD (Seasonal Affective Disorder.) There is a reason that depression is more significant in the colder seasons. The loss of blue light makes it difficult to regulate a healthy circadian rhythm. The average length of circadian rhythms is 24 ¼ hours; introducing blue light from other sources besides the sun disrupts this natural rhythm.


Blue light can be beneficial in specific quantities and at certain times but knowing when and how to use blue light to aid your body is essential, or the results can be detrimental. While the technology we use has its numerous advantages, it is critical also to understand the risks.


Heiting, Gary. (2017). All About Vision. Blue Light: It’s Both Bad and Good for You. Retrieved from https://www.allaboutvision.com/cvs/blue-light.htm.

Harvard Health Publishing. (2018). Blue Light has a Dark Side. Retrieved from https://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s