We all know the difference between light and dark, day and night. Most of us prefer and even need darkness to sleep, while others do better with a little nightlight.
But what about the color of lights? What kind of impact does that have on our sleep patterns?
Most experts agree that your best bet is a red light. Various studies show red to be a calming color, while other colors are harsher on the eyes. It is also said to be the one that least affects your natural sleep patterns.
In this article, we’ll explore this science a bit further to help you understand what color light is best for sleep and how the color of light you choose can impact the quality of your sleep.
How Does Light Impact Your Sleep?
We all know how horrifying it is when someone pulls up the blinds to shine the bright morning sun on your sleeping face. In a word, it’s disruptive, to say the least.
But scientifically, light affects three significant factors of sleep:
- Cardiac Rhythm
- Melatonin Production
- Sleep Cycles
Let’s take a closer look at these areas.
Your cardiac rhythm is defined as the electrical activity within your heart. Cardiac rhythm is responsible for maintaining tons of different processes throughout your body.
Did you know that your heart rate slows way down when you sleep? That’s because of cardiac rhythm.
But this rhythm can be impacted by light exposure. Your brain interprets light exposure through the eyes. It then tells the rest of your body what time of day it is, and your body’s organs respond accordingly.
In short, your cardiac rhythm is conditioned to respond to sunrise and sunset with natural lighting. But the presence of other light sources can interrupt this pattern and affect your sleep.
Melatonin production is closely related to your cardiac rhythm. Melatonin is a hormone. Your brain produces it in response to darkness and works with the schedule of your internal clock; i.e., your cardiac rhythm.
Because your melatonin production takes darkness as its cue, additional light at nighttime can slow or even block the hormone from its usual functions – thus, impeding sleep.
The presence of light during the night can lastly interrupt your natural sleep cycles. During an average night of sleep, a person will go through anywhere from four to six sleep cycles.
These cycles make it possible for you to adequately rest your body, as each stage serves different purposes.
When your sleep cycles are interrupted, you’re not getting high-quality sleep. Light can cause you to wake up during the night and prevent healthy, deep sleep.
What Color Light is Best for Sleep?
Most sleep experts will tell you that you get the best quality sleep when you sleep in the dark. But some people prefer to have some kind of small light, whether it’s due to fear of darkness or the idea of being able to see should you wake up during the night.
So if you need to have a light of some sort on, or you’re interested in the idea of light therapy, you should at least use the right color.
Some researchers believe that there’s evidence to suggest that lights close to the color red can improve melatonin production. However, there’s not enough solid evidence available right now to say that for sure.
There have been studies done – such as this one – that indicate red light could potentially improve sleep. Participants of this study received red light therapy for 30 minutes every night for 14 days.
The participants experienced improved sleep, melatonin levels, and endurance performance. But again, more research needs to be done to effectively prove this theory.
Some theories also state that pink light could improve sleep, since they contain red light waves, but this is another unproven concept.
Surprisingly enough, another study showed that individuals who chose their own color of lighting slept better than those assigned either a random color or white light.
This study essentially suggests that so long as you enjoy or feel calmed by a particular color, the light may actually help you fall asleep faster. In fact, the study even stated that those with their preferred light color fell asleep faster than those in the dark.
While, again, these studies are not completely conclusive, it does suggest that personal preference plays a role in your quality of sleep.
Light Colors That are Bad for Sleep
While studies show that red light is the best color for sleep, other colors may have an opposite effect. Here are some colors to avoid the next time you go shopping for a night light:
Studies show that the photoreceptors in your eyes are sensitive to any light that has wavelengths between 450 and 480 nanometers.
In short, blue light.
Blue light is the kind of light you see on all your screens: phones, tablets, laptops, TVs, and so forth. It has gained a seriously bad reputation in recent years, bolstering the sales of blue-light-blocking glasses to protect the eyes.
But during the day, blue light actually has some positive impacts. It can improve your mood, increase your reaction time, and even garner more attention.
When nighttime rolls around, blue light becomes more harmful. Any kind of light can minimize your melatonin production, but blue light is the worst of them all. Harvard studies show us that blue light not only reduces the production of melatonin significantly but also shifts cardiac rhythm.
White light most closely represents the full spectrum of light that comes from the sun. As we noted above, our bodies are designed on a 24-hour internal clock (cardiac rhythm), which is accustomed to the cycles of night and day.
So, white light isn’t great for sleeping, as it can trick your body’s internal clock into thinking it’s daytime.
While experts tend to recommend sleeping with the lights off, a dim red light will not disrupt your sleep patterns. It’s possible it even improves sleep.
Alternatively, you can choose a shade that makes you feel calm – just remember that it’s best to avoid blue and white light at night and near bedtime.
Armed with the right information, you can now create an environment that is conducive to sleep instead of disruptive, allowing you to finally get the rest you deserve.