Digital screen time is a big part of our lives.
About seven hours every day is spent looking at a screen. Many jobs require the use of a computer or tablet. We never leave the house without our smart phones. Our down time is spent checking out the latest posts on social media or watching videos online. During the COVID-19 pandemic, we relied on screen time even more to keep us amused during lockdowns, to do our jobs, or attend school.
Along with the increase in screen time has been an increase in blue light exposure. Blue light is one of several colors in the visible light spectrum. It is the color given off by our computers, TVs, tablets, and smartphones. Blue light is also given off by the sun.
There are both health benefits and harm from blue light. Moderate exposure can help improve mood, and brain function, including learning, thinking, memory, problem solving, attention, and decision making. This is because blue light activates areas of the brain responsible for these functions. Blue light from sun exposure can help regulate circadian rhythms, a 24-hour internal clock in our brain that regulates the cycles of sleepiness and alertness, also known as the sleep-wake cycle. When regulated properly, a person’s circadian rhythm can promote restful sleep.
Too much blue light or exposure during night hours is when it starts to become problematic, regardless of the source. It can damage the cells in the eye, creating vision problems, such as macular degeneration, cataracts, eye cancer, and growths on the white part of the eye. Children are especially at risk of vision problems, as their eyes naturally absorb more blue light than adults.
Exposure to blue light right before and during evening hours disrupts your circadian rhythm. Those with insomnia and difficulty staying asleep likely have this cycle out of alignment. The reason is that blue light blocks melatonin production. Melatonin is a hormone that your brain produces during darkness that help synchronizes the sleep-wake cycle. Melatonin also interacts with other hormones in the body that regulate aging, Alzheimer’s disease, Parkinson’s disease, and even menstrual cycles.
Protect yourself from natural blue light overexposure when outdoors. Wear sunglasses with 100% UV or UV400 protection. While polarized lenses reflect glare, not all brands block UV light absorption. Check the manufacturer details if the lenses provide this protection. Certain colored lenses, such as those orange- or yellow-colored, may block out the blue light. These colored lenses are usually marketed to fishermen, hunters, pilots, and those in jobs with high levels of sun exposure.
Limiting your screen time is the easiest way to protect from overexposure to digital blue light. Power down your devices three hours before bedtime.
Follow the 20/20/20 guideline: after 20 minutes of using a digital device, focus on an object 20 feet away for 20 seconds then repeat. Buy a blue light screen protector for your computer or phone. It all may sound extreme, but better to be safe than sorry.