All your digital devices, from phones and tablets to computers, laptops and televisions, emit blue light. According to the Harvard Medical School, our exposure to blue light or blue wavelengths is increasing exponentially with digital devices becoming more easily available. These blue wavelengths are beneficial in small amounts during the daytime, Harvard experts believe, as they can boost the mood, attention span and speed up reaction times.
Effects of blue light on sleep and vision
However, exposure to blue light during the evenings and especially during night time has more adverse effects than benefits. Many studies indicate that blue light exposure during nighttime can disrupt the circadian rhythm and cause sleep problems and disorders in the long run. A study published in Molecular Vision in 2016 reveals that the effect of blue light on eye physiology can also be quite damaging.
The study reveals that blue light exposure has a cumulative effect on the eyes and characteristics like wavelength, intensity, duration of exposure and time of day for the exposure also come into play. LEDs with an emission peak of less than 450 nanometres can be harmful to the eye in the short run as well as the long run, while those in the range of 470-480 nanometres can be harmful in the long run. High exposure to blue light can also cause the early onset of age-related macular degeneration.
The benefits of blue-light filtering glasses
A new study published in the Journal of Applied Psychology reveals that wearing blue-light filtering glasses while being exposed to LED screens and digital devices can improve sleep and thereby productivity the next day. The researchers collected data from 63 company managers and 67 call centre employees at the Brazil-based offices of a US multinational financial firm to evaluate blue light exposure and task performance. The participants were randomly chosen to test glasses that had blue-light filters and others with normal lenses.
The researchers found that blue-light filtering glasses created a form of darkness, which in turn improves sleep quantity and quality. Participants who got more sleep also showed physiological improvements, attitudinal changes that increased their work engagement, task performance and non-task performance.
This study indicates that wearing blue-light filtering glasses can counter many effects of blue light exposure and improve your health. These blue-light filtering glasses are easily available all over the world and can be easily accessed if you visit your ophthalmologist or any company that makes vision-correcting or remedial glasses.
For more information, read our article on How to improve eyesight.
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