Blue Light

Blue light is the visible light at end of the blue spectrum. Blue light is not as energetic as ultraviolet (UV) light, the main concern is that high doses of blue light may cause more cellular damage than longer wavelengths of visible light (which you see as the colors red through green). Furthermore, exposure to blue light has an impact on your sleep-wake cycle. 

This increased blue light exposure from LED lights, television, smart phones, tablets, and laptop computers raises concerns about the effects it may have on the sleep-wake cycle and the damages to the eyes that it may have. 

Considering the entire light spectrum, blue light has the shortest wavelengths that are detectable by the human eye. The sun has historically been the only source of blue light until the rise of technology. What was once natural blue light has turned into artificial that causes damages to the retina. This exposure to high levels of blue light is a cause for concern. Below is the light spectrum chart to show where blue light falls:

• Red: 625–740 nanometers
• Orange: 590–625 nanometers
• Yellow: 565–590 nanometers
• Green: 520–565 nanometers
• Cyan: 500–520 nanometers
• Blue: 435–500 nanometers
• Violet: 380–435 nanometers

Exposure to blue light is detected by the eyes and signals the pineal gland to suppress the secretion of the hormone melatonin. Melatonin is a sleep hormone that helps to regulate your circadian rhythm. With melatonin suppressed, you remain awake, alert, and able to go about your daily tasks and think clearly. Exposure to blue light in the evening and at night might continue to suppress melatonin, resulting in a disruption of the sleep-wake cycle. Minimizing the effects of blue light will improve your overall health.