British Report: LED Exposure at Night More Disruptive than Incandescent

An interesting development out of England.  The Telegraph is reporting that exposure to artificial light during the evening disrupts our natural 24-hour body clock or "circadian rhythm" and leaves us checking emails or watching television at night when we should be sleeping.  The report also says that this disturbs our bodies even more because the blue light used in television, computer and tablet screens is even more disruptive to sleep than traditional incandescent lighting.

The Telegraph cites a report in the journal Nature by Professor Charles Czeisler, of the Division of Sleep Medicine at Harvard University, said light "affects our circadian rhythms more powerfully than any drug".

The study noted as well as allowing us to see, our eyes help keep our body clock in tune by sensing the time of day and allowing our bodies to adjust themselves accordingly.

A member of the Sleep Research Society, American Academy of Sleep Medicine and American Physiological Society among others, Czeisler said that exposure to artificial light during the hours of darkness activates arousal-promoting brain cells and suppresses the release of the sleep-inducing hormone melatonin.

Our bodies evolved to reach a peak of energy not in the morning but in mid-afternoon, giving us a "second wind" that keeps us going throughout the evening, he said.

But disrupting the body clock with artificial light tells the brain it is still "daytime", meaning the second wind is pushed back by several hours.

"As a result, many people are still checking email, doing homework or watching TV at midnight, with hardly a clue that it is the middle of the solar night," Czeisler said. "Technology has effectively decoupled us from the natural 24-hour day to which our bodies evolved, driving us to go to bed later."

He added in the Nature report that energy-efficient light bulbs and LED light used in computer and television screens is making the problem worse because it is rich in blue light, to which our eyes are most sensitive.

While the move from incandescents to more energy efficient sources of light continues across the globe, Czeisler remains wary of the prevalence of LED use which are already in our laptops, televisions, and cellphones, While more studies on the subject are ongoing, he keeps gadgets and televisions out of his bedroom-just in case.

Interestingly enough, a study from the Rensselaer Polytechnic Institute Lighting Research Center found that looking at a backlit screen, like those on iPads and other tablets, can lead to sleeplessness. The findings of that study was published last fall in the journal-Applied Ergonomics.


And the show goes on. 

Give GET, LLC a call or drop us a line to discuss bringing an LED solution to your respective building or facility-we'll leave a solution on the lights in your respective bedrooms up to you.