How Does Blue Light Affect Sleep

The featured image of a blog article about blue light and sleep

“Keep electronics out of your bedroom.” 

“Wear blue light-blocking glasses when working at your computer or using for phone for extended periods.” 

The warnings about blue light from screens are constant, chirping at us from all different angles. However, many people need to take heed of these suggestions and pay attention to the effects of blue light. A significant number of people are adversely affecting their bodies and sleep. 

Why Blue Light Effects Sleep 

Blue light is a short-wavelength, high-energy color on the visible spectrum. As part of the natural electromagnetic energy spectrum, the sun is the most prominent emission source of blue light. Televisions, smartphones, tablets, computer screens, and LED bulbs also emit it. 

Humans need moderate amounts of blue light for good health. There is a direct, significant relationship between blue light and melatonin production in the body.  

Melatonin is naturally produced in the pineal gland and released in response to daylight and darkness. Throughout the day, the hormone fluctuates in concentration. Its primary function is to aid in timing the body’s circadian rhythm and sleep. The higher the concentration, the more tired the body feels; the lower the concentration, the less tired it feels.

Light is the most potent resetting cue for melatonin production and our circadian rhythms. When we wake up, and the sun comes up, we are exposed to blue light from sunlight. This blue light exposure causes melatonin production to decrease. In turn, our bodies feel alert and stimulated. 

So, during the day, blue light exposure is helpful. The wavelengths improve our mood, boost attention spans, and help reaction times. 

Then, as the sun starts going down for the evening and the retinas in your eyes detect waning light, melatonin production increases in response to the drop in blue light exposure. This rise in melatonin serves to help the body start to get sleepy and prepare for bed. Your body also starts lowering its core temperature.

A picture of a melatonin molecule against a pink background

The Rise In Blue Light Exposure

Historically, the human body’s sleep cycle was coordinated with the sun's rising and setting. Back then, and still to this day, most people wake up as the sun is coming up in the morning and go to bed after it sets at night. Biological clocks were kept in sync with the sun because of the fluctuating melatonin levels.

However, we’re not throwing our circadian rhythms off by altering our blue light exposure, and our sleep is suffering significantly.

Before the advent of the lightbulb, people relied on the sun as their primary lighting source. They got up with the sun in the morning, worked all day when it was bright, and spent evenings in a candlelit glow or relative darkness. After sunset, melatonin production increased, and people naturally got tired earlier in the evening. 

Now, after sunset, we light up our homes with artificial lights and spend hours staring at a tv, laptop, or smartphone until bedtime. 

We take all this light for granted but dearly pay the price for the brightness. Instead of experiencing a natural, earlier rise in melatonin levels, our retinas now receive blue light no matter the time of day. This artificial light confuses the body, disrupts our sleep patterns, and affects our health. 

A picture of a bedroom at night with a lot off light that throws off blue light

How to Counteract Blue Light Effects

When the sun starts setting, you want your body to start producing melatonin. In the couple of hours before sleep, you can do things to help minimize your blue light exposure and keep it from wreaking havoc on your sleep schedule. 

Avoid Electronics Before Bed

First and foremost, the best way to stop blue light from keeping you up at night is to avoid all electronics and screens for at least one hour before bed. Yes, that means no scrolling social media or reading the news on your phone after you get comfortable under the covers.

To help you get into the routine of avoiding screens, here are some tips you can use:

  • Set an alarm about two hours before bedtime, reminding you to shut devices down soon.
  • Keep your cell phone and laptop charger outside your bedroom. You won’t be tempted to continue scrolling or working when you plug them in for the night.
  • Take the television out of the bedroom. Without it there, you won’t be tempted to turn it on to help you fall asleep.

It is a habit that gets easier with time, and when you start feeling better because you’re sleeping better, you’ll want to keep going.

A woman using a tablet at night increases her blue light exposure

Change Your Light Bulbs

Switch out the bulbs in the bedside table lamp to ones that emit more orange or red light instead of blue. Standard incandescent bulbs emit light that closely resembles sunset. They cast out very little blue light. You can also purchase specialty LEDs with little to no blue light in their spectrum.

Wear Blue-Light-Blocking Glasses

Researchers at the University of Toronto examined melatonin levels of people wearing blue-light-blocking goggles while exposed to bright indoor light and people exposed to dim indoor light without goggles. The melatonin levels of the two groups were about the same, strengthening the hypothesis that blue light potentially suppresses melatonin.

Artificial light is part of society now, and our homes are filled with it. But a pair of inexpensive blue blockers can keep your eyes from seeing blue light in the evening and your melatonin levels from being suppressed. There are many styles available to purchase online and in stores.

An older woman in bed wearing blue light filtering glasses as she reads her ipad

Adjust Settings On Your Handheld Devices

Lastly, switch the settings on your phone or computer to dim the screen and decrease blue light exposure before bed. If using this strategy, keep yourself from turning up the screen brightness to compensate. Otherwise, it defeats the purpose.

  • On an Apple Device: Settings ➞ Display & Brightness ➞ Night Shift 
  • On an  Android Device: Settings ➞ Display ➞ Night Light
  • On a Computer: download f.lux

Expose Yourself to Bright Light During the Day

During the day, one of the best things you can do is expose yourself to as much bright light as possible. Doing so will boost your mood and alertness and improve your ability to sleep at night.

A woman sitting in a day room to expose herself to light

Consider Taking a Melatonin Supplement

If you still struggle to fall asleep, consider taking a melatonin supplement before bed. Evidence suggests taking a supplement before bed decreased the time it took study participants to fall asleep and helped them sleep longer. 

Melatonin is available over the counter and comes in many forms and dosages. Make sure to take the correct dosage, or it could cause more damage to your circadian rhythm than help it. 

In our store, we also have a sleep supplement with adaptogens, such as reishi mushroom, and the optimal dosage of melatonin to support sleep. Make sure to check it out!

Always check with your doctor or pharmacist before taking any supplements if you are on prescription medication to rule out any adverse effects. 

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