- Researchers investigate the effects of light in a common species of fly, Drosophila melanogaster.
- Not only blue light damages retinas but also cells in the brain.
- Daily exposure could accelerate aging, even if blue light doesn’t reach eyes.
Although light is essential for life, prolonged exposure to artificial light can raise health concerns. Humans are now being exposed to increased amounts of blue spectrum generated by LEDs.
LEDs have led to new sensors and displays, and they are now available across infrared, ultraviolet, and visible wavelengths, with high light output. Since LED technologies are relatively new, its long-term effects (exposure to blue light) are not well-studied.
Recently, researchers at Oregon State University analyzed the effects of light in the model organism, Drosophila melanogaster. It’s a species of fly commonly used for biological research in genetics, microbial pathogenesis, and physiology.
The Experiment
The research team exposed these flies to daily cycles of 12-hour darkness and 12-hour blue LED (similar to the prevalent blue wavelength in devices such as laptops and smartphones). Another group of flies was kept in complete darkness and in light with the blue wavelengths filtered out.
They found that retinal cells and brain neurons of the flies exposed to blue light were damaged. In fact, their common behaviors, such as their ability to climb walls, were impaired. The blue light was also associated with accelerated aging.
They also experimented with mutants that don’t develop eyes. Those eyeless files exhibited locomotion impairments and brain damage. This suggests that blue light can harm the brain to some extent even if it doesn’t reach eyes.
Researchers then analyzed gene expression in old flies and discovered that protective, stress-response genes were activated when flies were exposed to natural light. The light (with filtered blue color) slightly reduced flies’ lifespan. The blue light alone, however, shortened their lifespan aggressively.
Reference: Nature | DOI:10.1038/s41514-019-0038-6 | Oregon State University
Increased Exposure To Artificial Light
Natural light is essential for daily physiological processes, including hormone production, cell regeneration, and brain wave activity.
There are, however, multiple studies that show increased exposure to artificial light could lead to circadian and sleep disorders. And with the extensive use of LEDs in modern devices, humans are subjected to increasing amounts of blue light. But since the technology is relatively new, its effects across the human lifespan is yet to be discovered.
In the near future, advances in medicine and technology could work together to find solutions to these harmful effects of blue light. It is possible to develop devices that use a healthier spectrum of light, which not only improves sleeping cycles but overall health.
Read: Vision-Enhancing Nanodrops Could Replace Eyeglasses
However, such advanced devices aren’t coming soon. In the meantime, people can use amber glasses that filter out blue light and protect retinas, or they can turn on the ‘night-shift’ mode in which devices emit less blue light resulting in less sleep interference.
