Spending too much time on your phone could directly impact how long you live, scientists say

SPENDING too much time scrolling on your phone could directly impact your lifespan, scientists have said.

Most of us are guilty of a little too much screen time, and it’s not the first time research has warned of its potential harms.

The average adult will spend the equivalent of 34 years of their lives staring at screens, shocking surveys suggest.

The latest study investigated how light exposure to eyes contributes to how long someone lives for.

Buck Institute for Research on Aging looked at fruit flies - an insect commonly used by scientists because it is considered to have similar biological processes to humans.

It was a “surprise” to the researchers that the eye can “directly regulate” lifespan, said lead author Dr Brian Hodge. 

The connection lies in circadian rhythms - the body's 24-hour clock.

Circadian rhythms regulate bodily functions across a day, adapting to light and temperature as the sun rises and sets.

Depending on daylight, circadian rhythms control hormones to make us sleepy, hungry or to wake-up.

These rhythms can be thrown off by our behavious, such as exposure to light during night time by watching TV or working shifts.

The researchers found that too much light exposure to the eyes may disrupt the circadian rhythm - which spells trouble for health.

Senior author Professor Pankaj Kapahi said: “Staring at computer and phone screens, and being exposed to light pollution well into the night are conditions very disturbing for circadian clocks.

“It messes up protection for the eye and that could have consequences beyond just the vision, damaging the rest of the body and the brain.”

The research group previously found that restricting a fruit fly’s diet made significant changes to their circadian rhythms, and added onto their lifespan.

They wanted to find out why, and looked at which genes work in a clock-like fashion, finding multiple. 

Not only were they activated the most with dietary restriction, but they all seemed to be coming from the eye.

Specifically from photoreceptors, the specialised neurons in the retina of the eye that respond to light.

They then investigated whether the genes in the eye influence lifespan, finding that they do.

Prof Kapahi suggested light in itself can cause photoreceptor degeneration which can cause inflammation.

He said “dysfunction of the eye can actually drive problems in other tissues”.

Over long periods of time, it could worsen a variety of common chronic diseases. 

This was proven by an experiment in which flies were kept in constant darkness, in which flies lived for longer.

Prof Kapahi said: “We always think of the eye as something that serves us, to provide vision. 

“We don't think of it as something that must be protected to protect the whole organism.”

Whether these findings apply directly to humans is unknown, but Dr Hodge suggested circadian rhythm were key to ageing.

He added that it may be that humans could help maintain vision by activating the clocks within our eyes. 

“It might be through diet, drugs, lifestyle changes… A lot of really interesting research lies ahead,” he said.