High-energy blue light is making a buzz as more and more people are becoming aware of how it impacts eye health and more. With exposure from the sun, energy-efficient indoor lighting sources, and the almost constant use of digital devices, the need to protect the eyes is a must. In fact, people spend as much as 10 hours or more a day using digital devices.
Blue light is a component of visible light and makes up some of the highest energy that enters the eye. Sunlight is the largest source of blue light but it’s not the only source. And what’s changed over the past two decades is that most people spend more time under artificial lighting, working in front of computer screens, interacting with smartphones and watching television. Even though the light emitted from these devices is substantially less than natural sunlight, their usage has grown substantially. In many cases, people may spend longer on screens than they do sleeping. Children and teens can spend more time consuming digital media than time spent going to school — up to nine hours daily. This type of light penetrates deep in the eye and with short-term exposure leading to “computer vision syndrome” — a condition characterized by eye fatigue, eye strain and headaches. Long-term exposure can contribute to a gradual loss of visual function. The concerns around excessive exposure to blue light has other health implications as well.
Blue Light and Sleep Disruption Connection
It is hard for many people to resist the urge to “check in” with their phone or tablet before bedtime and this could be contributing to poor sleep quality. Blue light is unique because it helps regulate the circadian rhythm — the biological clock that signals sleep/wake cycles. With indoor lighting sources such as LED and CFL becoming more popular as well as technology use before bedtime, these blue-light-emitting devices can inhibit melatonin — a hormone that signals the body to sleep — and trick the brain into thinking it is daytime. The result is a delay in the time it takes to fall asleep and the quality of sleep itself. Poor sleep contributes to increased stress levels that impact mental and physical health, productivity, brain and heart health, immune function and even weight gain.
What Science Tells Us
Out of the more than 600 carotenoids found in nature, only three — lutein and the two zeaxanthin isomers — RR-zeaxanthin and RS (meso)-zeaxanthin — are found in the eye where they form a protective layer in the macula. The macula is the area of the retina responsible for the highest visual performance but also the area most susceptible to the harmful effects of blue light. Healthy eyes require all three macular carotenoids for protection and supporting visual performance and dietary intake or supplementation is the only way to get sufficient levels of these important nutrients. Given that dietary intake is far below the levels needed to support eye health, supplementation is a practical solution.
A recent study entitled, Effects of macular carotenoid supplementation on visual performance, sleep quality, and adverse physical symptoms in those with high screen time exposure, published in Foods 2017, demonstrated that supplementation of all three macular carotenoids improves eye health and performance including: visual processing speed — how fast your brain processes information that your eyes see; contrast sensitivity — the ability to perceive differences between an object and its background; disability glare — the ability to see clearly in bright light conditions; photo-stress recovery — how quickly your eyes recover from sudden bursts of bright light. Additionally, the study showed significant improvement in headache frequency, eye strain, eye fatigue and sleep quality. With “screen time” increasing and technology unceasingly advancing, our eyes will continue to be bombarded with high-energy blue light. Supplementation with Lutein and zeaxanthin is a simple solution to protect our eyes and improve sleep quality.
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