How Does Blue Light Affect Your Sleep?

If you have difficulty falling asleep at night, it could be due to overexposure to blue light emitted by electronic devices. This light can trick the brain, making it think it’s daytime, stimulating the brain when it should be winding down. In today’s article, we will go over what blue light is, the health benefits and risks of blue light, examples of blue light, and how blue light can affect your sleep schedule. 

What Is Blue Light?

Blue light is one of the many visible lights the human eye can see. It is a high-energy light and is commonly referred to as HEV light. Blue light is a short wavelength, meaning it produces higher amounts of energy. When it comes to visible and non-visible light, the shorter the wavelength, the higher the energy. 

Unlike some of the other forms of light visible to the human eye, our eyes cannot effectively filter blue light. This means more can pass through the eye to the retina. There are both health benefits and concerns when it comes to blue light. Throughout the article, we will discuss the potential downsides of blue light and how you can combat it. 

Potential Health Benefits of Blue Light

While you may think blue light exposure is a negative thing, it can actually have health benefits. Where concerns arise is exposure to blue light from electronic devices. But most of our blue light exposure is from the sun. Here are some of the health benefits of natural blue light exposure:

  • It can boost alertness, improve memory and cognitive function, and improve mood
  • It can help regulate circadian rhythm. Exposure to blue light during daytime hours can help maintain a healthy circadian rhythm. That’s why exposure to these lights at night can make it difficult to fall asleep
  • Children who don’t have enough exposure to natural blue light from the sun could experience issues with the growth and development of the eyes and vision. Studies show a deficiency in blue light exposure could contribute to the recent increase in myopia/nearsightedness

While there are some concerns about the health drawbacks of artificial blue light, it’s important to remember that natural blue light is important for our health. 

Is Blue Light Harmful?

Experts believe that too much exposure to electronic devices can be harmful to our health. Although a very small percentage of our exposure to blue light is from screens, there are still some long-term concerns. This is especially true when it comes to too much screen time and screens being too close to the face. 

According to a study by the Vision Council, 80% of American adults use digital devices more than two hours per day, nearly 67% use two or more devices at once, while 59% experience symptoms of digital eye strain. Constant exposure to blue light has the potential to damage retinal cells and cause vision problems such as age-related macular degeneration. It can also lead to cataracts, eye cancer, and growths on the clear covering over the white part of the eye. 

Studies also show that we are less likely to blink when using digital devices. This can lead to dry eyes and neck stiffness. Other signs of eye strain include headaches, blurred vision, and neck and shoulder pain. The Vision Council estimates that 27% to 35% of Americans experience one of the symptoms listed above after using a digital device. 

How Does Blue Light Affect Your Sleep?

As mentioned earlier, blue light has an effect on our circadian rhythm. Exposure to natural blue light during the day is a good thing, as it can help promote healthy circadian rhythms. However, exposure to this light late at night can make it difficult to fall asleep. That’s because blue light stimulates parts of the brain that make us feel alert, which elevates our body temperature and heart rate. During the day it can improve performance and attention, but after the sun sets, it can confuse the body. 

Blue light exposure can actually help treat several different sleep disorders. Disorders such as circadian rhythm disorders can happen when someone’s circadian rhythm isn’t in alignment with the environment. Light therapy and blue light can help realign the body’s circadian rhythms, improving sleep. 

Exposure to blue light can suppress the body’s release of melatonin, the hormone that makes us feel drowsy. While this can help us during the day, when we need the energy, it becomes a problem during the night. Nocturnal blue light exposure can trick the brain into thinking it’s still daytime, disrupting our circadian rhythm, leaving us feeling alert instead of tired. 

Due to increased amounts of light before bedtime, many Americans are experiencing chronic misalignment of circadian rhythms. This can lead to negative health impacts including metabolic disorders and mental health conditions such as depression and anxiety. This is why it’s important to understand where blue light comes from and how you can limit your exposure at night time. 

Examples of Blue Light

Understanding where blue light comes from can help you understand what devices you should avoid late at night. The sun emits blue light, which we need during the day. However, many of the devices we use also emit blue light, which can cause problems at night. Here are some of the devices that emit blue light:

  • Smartphones and tablets - These devices put out more blue light than any other. However, most of these devices come with a ‘night mode,’ which gives your screen an orange tint with longer wavelength light
  • Laptops and computer monitors - Think of these devices as larger smartphones and tablets. They send out the same type of light. Just like with smartphones and tablets, these devices may have a night mode
  • Fluorescent and LED Light Bulbs - These use less electricity than traditional incandescent light bulbs, but they emit more blue light. Some of these bulbs are coated to put out warmer light
  • LED televisions - Most flat-screen televisions are backlit with LED lighting. Newer TVs may have an internal blue-light filter that you can switch on
  • E-readers - Digital readers are great devices, but they can make it difficult to fall asleep. Some e-readers have a setting to reduce blue light
  • Handheld gaming systems - Just like other digital screens, handheld gaming systems emit blue light. Experts suggest limiting your children’s exposure to blue light before bed, as their eyes can filter blue light as well as adults

How To Manage Blue Light

Now that we have a better understanding of what devices emit blue light, it’s important to better understand how we can limit our exposure to blue light. Here are some of the ways you can manage the blue light signals you receive late at night:

  • Cut down on screen time - The easiest way to manage blue light is by taking regular breaks from computer or TV screens. Every 20 minutes, you should look away from your screen and focus on an object 20 feet away. Do this for at least 20 seconds
  • Take a break from blue light at night - Screen breaks are very important in the evening. Try to power down your device at least three hours before you go to bed. This will help stop blue light from affecting your body’s release of the sleep hormone melatonin
  • Get new glasses - Blue light glasses have grown in popularity lately, as these glasses come with special lenses that can lower exposure. The yellow-tinted lenses increase the contrast of your screen, filtering blue light and easing digital eye strain. More research is needed, but many believe these glasses do a good job blocking nocturnal blue light
  • Add a filter to your screen - In today’s day and age, most devices that emit blue light have filter options to limit the amount of blue light they emit. These settings lower the brightness of your screen. These settings can ease eye strain
  • Supplements - One small study found that taking supplements with lutein and zeaxanthin for 6 months eased eyestrain, poor sleep quality, and headaches from excessive screen time. You should always speak with your healthcare provider before starting a supplement regimen 

If you are having a difficult time sleeping at night, you should try some of the methods listed above. 


With our reliance on technology only growing by the day, it’s next to impossible to avoid devices that emit blue light. This artificial light can lead to sleep issues and other health issues. Limiting our exposure to these lights and avoiding devices that emit blue light can help us fall asleep at night and, more importantly, stay asleep.