Light can be considered the enemy of sleep. After all, you’re far more likely to doze off in a dark room than you are in the presence of bright lights. However, not all light is created equal. While some kinds of light may keep you up at night, there are others that can actually be considered sleep-friendly.


According to Dr. Michael Grandner, a member of the Behavioral Sleep Medicine Program at the University of Pennsylvania, one of the biggest mistakes that you can make when you’re having trouble getting to bed, or when you wake up in the middle of the night and plan on heading back to bed, is turning on the light. This notion goes directly with the idea that light and sleep don’t mix. Grandner states:


“Light hits the eyes and it travels from your eyes to the brain. In your brain, there’s a clock that uses this information from light to try and set all the different rhythms in your body. It’s expecting it to be dark at night and bright during the day, and it uses that information. But when it gets information that it’s not expecting, it can throw off the clock.”


However, Grandner goes on to explain that not all light is unconducive to sleep, and the difference between lights that disrupt sleep and lights that promote sleep comes down to color.


According to Garndner, bright lights with blueish/greenish hues are likely to disrupt sleep or cause you to sleep uneasily because your body associates this light with daytime (

According to Grandner, bright lights with blue or green hues are likely to disrupt sleep or cause you to sleep uneasily because your body associates this light with daytime, unlike red, orange, and green hues which may promote sleep (

When your eyes are exposed to blueish-greenish light, they associate that with daytime. Your body begins reacting in response to that trigger, thus making this particular hue of light likely to keep you awake and alert. Meanwhile, reddish, yellowish, or orangish lights are associated with the evening and are thus more likely to make you tired or make you get to sleep more easily.


That being said, if you have to turn a light on in the middle of the night, or if you prefer to sleep with a small night-light in your room, the best way to ensure that the light doesn’t keep you from falling asleep is to make sure you’re using red, yellow, and orange lights and bulbs which will be conducive to sleep.


This contrast between the different effects of varying hues of light on sleep provides an interesting reflection on how colors can initiate certain responses in our minds and bodies and can serve as triggers for different kinds of behavior, demonstrating that colors are about so much more than aesthetics.


Do you feel like your body reacts differently in the presence of difference hues of light? Share your thoughts below or tweet me @tamarahoumi