Health Desk- 17 Dec 2019: The idea artificial light from screens is keeping people awake at night is flawed, say scientists who have been studying the best type of lighting to nod off to.
According to the researchers, from Manchester University, this blue light from devices is not the main problem.
They exposed mice to different light settings to study the impact.
The controversial findings, in Current Biology journal, suggest the answer lies in how warm and bright a light is.
Everyone has a natural, daily wake-sleep cycle. Their body clock synchronises with the environment so they are alert in the daytime and sleepy at night.
But experts have long suspected exposure to artificial light might be upsetting this alignment.
And there is a popular view artificial blue light - the type that comes from computer screens and mobile phones - has a particularly strong effect.
The team did tests on mice, fixing the brightness to high or low and switching the colour from blue to yellow.
Bright light of either colour was stimulating, rather than restful, as expected. But when the light was dimmed, blue light was more restful than yellow light.
Lead researcher Dr Tim Brown said the findings matched what happened in the natural world, with bright, warm daylight.
Conversely, bright white or yellow light was better for staying awake and alert.
Courtesy: BBC Health