Is Your Smart Phone Accelerating Your Aging?

Researchers at Oregon State
University found prolonged exposure to blue light, such as that which emanates
from your phone, computer and household fixtures, could be affecting your
longevity, even if it’s not shining in your eyes.

The new study suggests that the blue
wavelengths produced by light-emitting diodes damage cells in the brain as well
as retinas.

The study,
published in Aging and Mechanisms of Disease, involved a widely used organism,
Drosophila melanogaster, the common fruit fly, an important model organism
because of the cellular and developmental mechanisms it shares with other
animals and humans.

Jaga Giebultowicz, a researcher in
the OSU College of Science who studies biological clocks, led a research
collaboration that examined how flies responded to daily 12-hour exposures to
blue LED light – similar to the prevalent blue wavelength in devices like
phones and tablets – and found that the light accelerated aging.

Flies subjected to daily cycles of
12 hours in light and 12 hours in darkness had shorter lives compared to flies
kept in total darkness or those kept in light with the blue wavelengths
filtered out. The flies exposed to blue light showed damage to their retinal
cells and brain neurons and had impaired locomotion – the flies’ ability to climb
the walls of their enclosures, a common behavior, was diminished.

Some of the flies in the experiment
were mutants that do not develop eyes, and even those eyeless flies displayed
brain damage and locomotion impairments, suggesting flies didn’t have to see
the light to be harmed by it.

“The fact that the light was
accelerating aging in the flies was very surprising to us at first,” said
Giebultowicz, a professor of integrative biology. “We’d measured expression of
some genes in old flies, and found that stress-response, protective genes were
expressed if flies were kept in light. We hypothesized that light was
regulating those genes. Then we started asking, what is it in the light that is
harmful to them, and we looked at the spectrum of light. It was very clear cut
that although light without blue slightly shortened their lifespan, just blue
light alone shortened their lifespan very dramatically.”

Natural light, Giebultowicz notes,
is crucial for the body’s circadian rhythm – the 24-hour cycle of physiological
processes such as brain wave activity, hormone production and cell regeneration
that are important factors in feeding and sleeping patterns.

“But there is evidence suggesting
that increased exposure to artificial light is a risk factor for sleep and circadian
disorders,” she said. “And with the prevalent use of LED lighting and device
displays, humans are subjected to increasing amounts of light in the blue
spectrum since commonly used LEDs emit a high fraction of blue light. But this
technology, LED lighting, even in most developed countries, has not been used
long enough to know its effects across the human lifespan.”

Giebultowicz says that the flies, if
given a choice, avoid blue light.

“We’re going to test if the same
signaling that causes them to escape blue light is involved in longevity,” she
said.

Eileen Chow, faculty research
assistant in Giebultowicz’s lab and co-first author of the study, notes that
advances in technology and medicine could work together to address the damaging
effects of light if this research eventually proves applicable to humans.

“Human lifespan has increased
dramatically over the past century as we’ve found ways to treat diseases, and
at the same time we have been spending more and more time with artificial
light,” she said. “As science looks for ways to help people be healthier as
they live longer, designing a healthier spectrum of light might be a
possibility, not just in terms of sleeping better but in terms of overall
health.”

In the meantime, there are a few
things people can do to help themselves that don’t involve sitting for hours in
darkness, the researchers say. Eyeglasses with amber lenses will filter out the
blue light and protect your retinas. And phones, laptops and other devices can
be set to block blue emissions.

“In the future, there may be phones
that auto-adjust their display based on the length of usage the phone
perceives,” said lead author Trevor Nash, a 2019 OSU Honors College graduate
who was a first-year undergraduate when the research began. “That kind of phone
might be difficult to make, but it would probably have a big impact on health.”

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