Excess blue light from phones, tablets may accelerate ageing: Study

Washington: Excessive blue light emitted by devices such as smartphones, computers and tablets may accelerate the ageing process of the body, according to a study conducted in fruit flies.

Previously, studies have linked too much screen use to disorders such as obesity and psychological problems.

"Excessive exposure to blue light from everyday devices, such as TVs, laptops, and phones, may have detrimental effects on a wide range of cells in our body, from skin and fat cells, to sensory neurons," said Jadwiga Giebultowicz, a professor at Oregon State University, US, and senior author of the study.

"We are the first to show that the levels of specific metabolites -- chemicals that are essential for cells to function correctly -- are altered in fruit flies exposed to blue light,” Giebultowicz said.

The study, published in the journal Frontiers in Aging, suggests that avoidance of excessive blue light exposure may be a good anti-ageing strategy.

The researchers have previously shown that fruit flies exposed to light "turn on" stress protective genes, and that those kept in constant darkness lived longer.

"To understand why high-energy blue light is responsible for accelerating ageing in fruit flies, we compared the levels of metabolites in flies exposed to blue light for two weeks to those kept in complete darkness," explained Giebultowicz.

Blue light exposure caused significant differences in the levels of metabolites measured by the researchers in the cells of fly heads.

In particular, they found that the levels of the metabolite succinate were increased, but glutamate levels were lowered.

Succinate is essential for producing the fuel for the function and growth of each cell. High levels of succinate after exposure to blue light can be compared to gas being in the pump but not getting into the car.

"Another troubling discovery was that molecules responsible for communication between neurons, such as glutamate, are at the lower level after blue light exposure,” Giebultowicz said.

The changes recorded by the researchers suggest that the cells are operating at suboptimal level, and this may cause their premature death, and further, explain their previous findings that blue light accelerates ageing.

"LEDs have become the main illumination in display screens such as phones, desktops and TVs, as well as ambient lighting, so humans in advanced societies are exposed to blue light through LED lighting during most of their waking hours," explained Giebultowicz.

"The signalling chemicals in the cells of flies and humans are the same, so the there is potential for negative effects of blue light on humans," Giebultowicz said.

The researchers will carry further work to study the effects of blue light directly on human cells.