What is Blue Light
It is no secret that overexposure to UV rays from the sun is damaging, but there are other lights that we should be concerned about. Blue light also referred to as high-energy visible light (HEV), is a part of the visible light spectrum, which is a segment of the electromagnetic spectrum that the human eye can see. The human eye is able to detect wavelengths from 380-700 nanometers and blue light vibrates at 380-500. It is the shortest wavelength and has the highest energy. Blue light is all around us, however, sunlight is the most significant source. There are artificial sources of blue light, including LEDs, fluorescent light bulbs, and many of our electronic screens such as televisions, computer screens, phones, etc.
It is important to note that blue light is not necessarily all bad, despite its negative reputation. Blue light boosts alertness, elevates mood, and helps with cognitive function as well as to regulate our circadian rhythms. However, too much exposure to blue light can be very unhealthy.
Negative effects of extended screen time
Computer vision syndrome (CVS), refers to a group of eye and vision-related problems that come from prolonged use of electronics emitting blue light. Some symptoms of (CVS) are:
Eye Strain and blurred vision: Long-term exposure to screens can trigger a slow degeneration of the retina. The eyes are constantly readjusting focus between the resting point of accommodation, where they want to be focused, and the front of the screen, where they should be focused; leading to eye strain.
Headaches: The eye is constantly readjusting to screens, which can trigger headaches.
Dry eye: Caused by a decrease in the blinking rate while staring at screens.
Neck and shoulder pain can be a result of poor posture when using an electronic device. This can be from sitting with the device in the lap, slouching on the couch, and/or not having proper back support. Flexing the neck forward for a prolonged period of time puts pressure on the spine, resulting in neck and shoulder pain.
Insomnia can be a negative result of excessive screen time. The blue light emitted from screen devices can suppress melatonin, the body’s sleep-inducing hormone, interfering with the body’s internal clock when overused.