How harmful Blue light can be?

Light with “blue” radiation is bad for you, not blue coloured light

Millions of years ago people lived in sync with nature.

When we lived in caves we didn’t have light bulbs and this somehow helped our circadian clocks to stay on track with the natural day and night cycles of the sun

Then people started using candles which have color temperature around 1800K which was still fine

The Incandescent light bulbs time was also good because the light emitted from this lightbulbs is with color temperature around 2800K.

Basically, the lower the color temperature the less blue light the light source emits.

In contrast, LED light bulbs and monitors both emit around 6500K.

Is it bad?

This is the intensity profile of an average LED light today. As you see, even though we perceive the colour as white (due to complex technical reasons), it is giving off the most intensity around the neighbourhood of 450 nm wavelength, aka “blue”.

You may know that the UV light is really bad for our eyes, but you probably don’t know that the blue light is also a big problem.

The bigger problem is actually that blue light enters deep into our eyes and it’s high energy light.

But,The problem is not the light or the blue. The problem is us.

If we model human eyes as simple frequency response models, we have primary photoreceptors for red, green, and blue. We naturally have the most receptors for green, followed by red, and then blue.

We have few blue receptors, so if we look at light with high blue intensity, then our receptors would be working overtime, hence our eyes feel tired. Over a long time, receptors will be desensitized aka worn out more easily.

blue light is said to be extremely harmful to the way we sleep, as it can very much interfere with our sleeping patterns, and in fact, it can worsen our quality of sleep by almost twice as much as any other form of light. And it also suppresses our production of melatonin by twice the amount, too.


If you experience this high level of sleep disruption on a regular basis, it will not only let you be awake at night, hence, it can eventually lead to severe health and wellbeing problems such as obesity, depression, cardiovascular disease, heart problems, a weakened immune system, slower metabolism and much more.

How to fix this?

Try to avoid light at night and if you just can’t avoid all light and need to get some work done on your PC

you can use Blue light blocking glasses to block both the Blue Light