July 27, 2023
The need for sunscreen to protect against UV exposure and cancer risk is mainstream knowledge. Lesser known is the impact of blue light or high-energy visible light (HEV) to the skin. A look at the research reveals...
On the light spectrum, blue light is right next to UV light which contributes to 90% of the visible signs of skin aging. The sun emits both UV and HEV light. Of concern is that someone working on a computer might not be aware of the exposure because they are indoors or might not think it requires sunscreen protection. This exposure can produce free radicals which break down collagen and elastin and create dark spots. There is one study that shows the hyperpigmentation produced by HEV light being darker and more difficult to eliminate than from other light sources. It is known that HEV light penetrates the skin more deeply. Skin penetration of UV light ranges from 100-400 nanometers and into epidermis and dermis layers. Deeper HEV light penetration ranges between 380-500 nanometers and penetrates the hypodermis. HEV light has been shown to initiate the inflammatory cascade, of particular concern for reactive skin conditions.
If you want to protect your skin from HEV light, not every sunscreen is effective. Physical sunscreen ingredients, such as zinc oxide, reflect the blue light away from skin and chemical sunscreens do not. Setting your devices to night mode also significantly switches blue light emissions to yellow light. Blue light blocking screens decrease the emission of HEV from devices such as computer screens and cell phones. If the screen is effective, you should see a blue reflection on the protective side when you hold the screen up to any light source with HEV light.
(We purchased a cell phone screen that did not pass this test. The second one passed and was an EyeJust screen. We have no affiliation with this company.)