For many people, interacting with digital screens is almost a necessity in our society. Smartphones, TVs, restaurant menus… the examples are abundant. With this increase in interaction with digital screens, some may wonder if it is worth taking into consideration how this screen time affects us on a day-to-day basis.
What is Blue Light?
Blue light, also known as high-energy visible (HEV) light, is a color in the visible light spectrum that can be seen by human eyes. These wavelengths of visible and non-visible light are measured in nanometers (nm), and, in general, the shorter the wavelength, the higher the energy. Blue light is a short wavelength, which means it produces higher amounts of energy.
Unlike other forms of light, the eyes cannot effectively filter blue light, so more can pass through the eye to the retina. Blue light produces both benefits and concerns for our eyes and overall health.
How It May Help
Evidence is growing that shows blue light can:
- Boost alertness
- Help memory
- Raise mood
- Improve attention span and reaction times
What are the Risks?
Eyes and Body
Screen time has been on the rise for the last 20 years and is now exceeding 13 hours per day on average. According to the Vision Council, many people experience eye discomfort and vision problems when using digital devices for extended periods.
Some symptoms that have been reported after longer periods of blue light exposure include:
- Eye strain
- Blurred vision
- Dry, irritated eyes
- Headaches
Blue Light and Sleep
Screen time, especially at night, is linked to poor sleep. The blue light from electronic devices can affect your circadian rhythm, or sleep cycle. This is what signals our brain to wake up when it should be winding down. In one study, as little as 2 hours of exposure to blue light at night slowed or stopped release of the sleep hormone melatonin. Powering down your digital devices at least a couple of hours before bedtime can help.
How to help reduce risks
You can’t avoid blue light completely (sunlight is also considered blue light), but there are ways to limit your exposure. They include:
Screen Time: Limiting screen time, especially before sleeping
Screen Filters: Using screen filters to lower blue light exposure
Computer Glasses: Wearing blue light-blocking glasses or glasses with anti-reflective lenses
Follow the 20-20-20 Rule: For every 20 minutes spent looking at a screen, a person should look at something 20 feet away for 20 seconds.
 Built-In Technology: Many laptops and monitors now have technology designed into the hardware, which helps reduce blue light emissions.