More people are now aware of the threat that blue light poses to the eye and the ability to get good, restful sleep. Researchers are now saying that the light may be doing more damage from protracted exposure by speeding up the aging process.
There are numerous devices these days that emit blue light and people are exposed to or cannot avoid using them in an average day. They include mobile phones, tablets, computer monitors, and televisions. People are increasingly being exposed to this light due to widespread use of light-emitting diode (LED) technology.
The long-term effects of LED lighting exposure on the lifespan of humans are currently not fully known. This is because the technology has not been around for a very long time.
Researchers at Oregon State University have now found evidence that suggests blue light may produce adverse effect on longevity in humans. This conclusion was based on observed effects on the common fruit fly, which has certain mechanisms in common with humans.
Findings from the new study showed that avoiding eye exposure to blue light is not sufficient to prevent its damaging effects.
“The fact that the light was accelerating aging in the flies was very surprising to us at first,” said lead researcher Jaga Giebultowicz, Ph.D, of the College of Science at Oregon State University. “It was very clear cut that although light without blue slightly shortened their lifespan, just blue light alone shortened their lifespan very dramatically.”
The new research was published recently in the journal Aging and Mechanisms of Disease.
Aging effects of blue light
Natural light plays a vital role in the regulation of the body’s circadian rhythm. It helps to ensure that key physiological processes, including brain wave activity and cell regeneration, run smoothly round the clock. These processes are crucial for regulation of feeding and sleeping patterns.
On the other hand, evidence suggests that artificial light disrupts these important processes. Blue wavelengths of light-emitting diodes, which are now ubiquitous, constitute a risk factor for sleep and circadian disorders, according to researchers.
Giebultowicz and her team found in the new study that daily exposure to blue light can accelerate aging.
The scientists made use of Drosophila melanogaster – the common fruit fly – as the model organism for their research. They evaluated the effects that 12-hour, daily blue light exposure produced in flies. After 12 hours of exposure each day, the organisms are kept in darkness for the remaining 12 hours.
Researchers observed that the blue-light exposed flies suffered damage not only to their retinal cells, but also to neurons in their brains. The organisms were also less able to climb their enclosures’ walls – they experienced reduced locomotion.
The flies that were exposed to blue wavelengths of light had shorter lifespan, compared to those kept in complete darkness or in light without blue wavelengths.
Giebultowicz and her colleagues noted that blue light can be harmful even when it is not reaching the eye. Some mutant flies without eyes that were included in the experiment also showed brain damage and impaired locomotion from exposure.
While carrying out their study, the researchers made an interesting observation that the flies attempted to keep away from blue light.
Giebultowicz revealed plan to investigate whether the signaling that makes the organisms to want to escape from blue light contributes to longevity.
A faculty research assistant in her lab, Eileen Chow, said scientists might be able to develop a healthier light spectrum to promote better sleep and improve overall health. But, first, there is need to determine if the findings are applicable to humans.
Trevor Nash, lead author and a 2019 Honors graduate of OSU, said phones that are capable of automatically adjusting their display on the basis of length of use might become available someday. However, he did acknowledge the difficulty that may be involved in coming up with such devices.
For now, researchers advise using eyeglasses that have amber lenses when using blue light-emitting devices for filtering purposes. Users can also set their devices to limit blue light emissions, if such have the capability.