Is our modern life with its inadequate exposure to natural light during the day and our preponderance of artificial light upsetting our natural biological clock and putting us at risk for disease?
The answer very well could be “yes,” says Richard Stevens, a UCONN Health Center cancer epidemiologist, who believes that the growing use of e-readers, tablets, and smart phones is upsetting our body’s natural sleep/wake cycle.
According to Stevens, these devices emit enough blue light when used in the evening to suppress the sleep-inducing hormone melatonin and disrupt the body's circadian rhythm, the biological mechanism that enables restful sleep.
"There's growing evidence that the long-term implications of this have ties to breast cancer, obesity, diabetes, and depression, and possibly other cancers,” said Stevens.
He cited a recent study that show people who use e-reader have delayed melatonin onset in the evening compared to those who read old fashioned paper books.
Incandescent lighting used to read traditional books by is less disruptive to the body’s biological rhythm than electronic devices, he said.
The article appears in the British journal Philosophical Transactions of the Royal Society B.
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