The most energising colour

Visible light spectrum
(Courtesy of Carolina Biology Supply Company via Flickr )

I’m guessing you’ve heard the phrase, ‘blue light is bad for you.’ In one way or another. But what exactly is making blue light the bad guy?

Turns out, compared to all the different coloured lights, blue light is the most energising.

All the colours we see have different wavelengths and therefore, different frequencies. The shorter the wavelength, the higher the frequency and the more energy the colour has. When we place all our colours on a spectrum, we see that blue is one of the most energetic colours we have.

This came as a surprise at first since I had a preconceived idea that warm colours like red and orange were energetic and the cool colours like blue reminded me more of the calm ocean and sky. The blue color of the skies is a prominent source of blue light. In fact, the bluish appearance of skies is actually a mechanism that keeps us awake during the day and sleepy when the sky turns dark.

This is until electronic devices came into play and we were able to access blue light even at night.

By turning on your laptop or staring at your phone screen at night, the high frequency blue light enters your eyes and causes you to become more alert and focused by suppressing a chemical known as melatonin. Melatonin is the main brain chemical that is responsible for making you sleepy and by suppressing it, we are effectively telling our brains that it is daytime.

In the study by Harvard Medical School, a group of people were exposed to blue light and another group of people were exposed to a lower frequency green light for 6.5 hours. The results showed that blue light suppresses melatonin twice as much as green light. Meaning that the group of people exposed to blue light had their biological clock disrupted by twice the amount of time than what the people exposed to green light experienced.

This just shows how much of a harm overexposure to blue light can be to our biological clock.

In an age of technology however, it is very much difficult to stay away from artificial blue light. Ever since lockdown hit, it has become even more challenging as everything we do has been inadvertently converted to online.

Good news though. Here are some tips that I would like to share with you.

If we refer back to our colour spectrum, right at the opposite end of blue light, we have the warmer colours such as red. Red has the lowest frequency and thus is the least energetic colour we have. In theory, the night shift mode built into our computers should minimize the harm.

It is important to note that all light suppresses melatonin just to different extents. But this should reduce melatonin suppression making it a little bit easier for you to fall asleep.

Good night.

Further reading

The inner clock – Blue light sets the human rhythm

Blue light from light-emitting diodes solicits a dose-dependent suppression of melatonin in humans

Out of the blue – New Scientist


6 Responses to “The most energising colour”

  1. Keina says:

    That might be why! Also, individuals will have different sensitivities to light, and generally, children are more sensitive compared to adults. Changing the colour to orange might work well!

  2. mkahirupan says:

    I always choose my night lamp in blue light mode instead of other colours, no wonder my kids can’t sleep easily each night 😀

  3. Keina says:

    Yes, it can definitely go both ways. Blue light on and sleepy chemicals suppressed, and blue light off and sleepy chemicals released.

  4. Keina says:

    Good to hear! I’ve started using it more often too!

  5. Joshua Sibbing says:

    I once heard that when your eyes stop seeing blue light your brain starts releasing a chemical that makes you sleepy. Super interesting, I should probably stop using my computer so late…

  6. Makie says:

    This was super interesting, Keina! Will definitely start using the night shift mode more often:)