Which is the best color light for reading at night? White or yellow? Warm or cool? Which color temperature? Which color light is best to read in bed without stressing your eyes, or without hurting your sleep?
Here is the short answer:
Best color light for reading at night, is warm tone or yellow color light. To be exact, it should be below 3000K on color temperature scale. Such light will be less stressful to your eyes. Plus, it will not disturb your sleep.
You can get that light by checking best warm color reading lights for bed of multiple types, or by simply selecting one from the best portable clip-on book lights. Another solution, is to keep all the lights in your room, but wear one best blue light blocking glasses that will block all the blue wavelengths that disturbs your sleep.
But, you might have some questions in your mind. Here are the answer to those.
Why warm or yellow color is good for sleep?
Warm color light in the evenings or at night, does not harm your melatonin production, like the white light or cool light does. That is why, with warm light exposure, you feel sleepy just as normal without any problems.
But, If you expose yourself to white/Blue light at night for just one hour, like when reading in bed, you decrease melatonin production, which will delay your sleep time upto 3 hours.
What is Melatonin?
Melatonin is a hormone which is responsible for your sleep. If there is more Melatonin production, you will feel more sleepy and vice versa.
One factor on which Melatonin production depends, is the exposure to blue light. When blue light falls on to your eyes, they send signal to brain and it restricts Melatonin’s production.
Why melatonin production affects sleep?
Melatonin production affects sleep because it is the nature’s way of syncing your cardiac Rhythm with the rest of the world, so that everything functions properly.
Actually, the nature has a mechanism to keep you awake at daytime, and make you feel sleepy after evening. This mechanism is controlled by the blue light in the surroundings.
When your eyes detect blue light in abundance, it sends signals to brain, that interprets them as day time.
And when there is dim or warm color light (which means less blue light) in the surrounding, your brain detects it as the evening or the night time, response accordingly.
What is color temperature?
In simple terms, color temperature is a scale, that tells the colour of the light, emitting from the bulb. You can also understand how much blue light is in the light, by seeing its colour temperature.
There is a range in color temperature, starting from 1800K and moving up to 6500K.
If you start from the heighest, 6500K is the coolest light with the most amount of blue light in it. This is useful, if you want to keep yourself awake and alert.
But if you are reading at night, then the best color temperature is below 3000K. This is what you call warm light, and if you move down further on the scale, then you will get amber coloured light, at 2000k or below.
For reading in bed, warm light, Amber light, or yellow color light with the color temperature below 3000k is ideal, as it does not interrupt your sleep cycles.
Why warm yellow color light does not disturbs sleep where blue light does?
Warm color light is perceived by the brain as the evening time or the night time. It is because, naturally, at that time the sun sets and the sky turns from Blue to warm Yellow color.
In the modern world, we expose our eyes to the blue light, even at night. Whether it is through 6500K light bulbs in the room, TV screens, or monitors, or cell phones.
Why warm light is less stressful to your eyes?
Research has shown that prolonged blue light exposure is so harmful, that it can cause permanent damage to your eyes, even blindness in a few cases. This is why, blue light is not only harmful for your sleep, but is also harmful for your eyes. But, warm light is less harmful, and less stressful to your eyes.
Does it only matter when reading at night time?
Yes, you need to be limiting the blue light exposure while reading at night time, only. Because at day time, you are constantly in the blue light atmospher, anyways. But, in this case, the Nature is responsible, and when nature does it, then it is only for your better.
What is the solution?
If you do not want yourself to be exposed to excessive blue light while reading at night, then you can do two things
- Read in warm or amber color light. Check best warm color reading lights for bed of multiple types, or simply select one from the best book lights.
- Get a blue light blocking glasses to be extra safe
While reading at night, the light must be bright enough to light up the book or kindle you are reading, such that the words are easily visible. Actually, the brightness is more important than color, if you are worried about your eyes.