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Reading Tablet, Computer, Smartphone or TV before Bed May Cause Cancer   

December 24, 2014
 - It is doubtless that e-readers, tablet, computer, smartphone digital television have considerably revolutionized the way people communicate and entertain themselves. And day by day new devices appear on the market, making life easier in term of communication and entertainment. But behind this technological sustainable progress, there are serious adverse effects on health. 


Reading these electronic devices right before bed can permanently disrupt sleep cycle and increase risk for prostate cancer and breast cancer, new study has found. Individuals who read on a screen of a tablet, computer, smartphone or television before going to bed feel less natural signs of fatigue and take longer to fall asleep, according to a to new research from Brigham and Women's Hospital in Boston, Massachusetts, published in the journal Proceedings of the National

During the study, the researchers observed a dozen people reading before bed, some on some type of electronic reading light, the other on paper (printed book). Important differences have been noted between the two groups. These electronic devices emit light to the face, causing users experience less natural signs of fatigue and take longer to fall asleep. Their

brains secrete less melatonin (hormone mainly released at night which plays a role in natural sleep-wake cycle), compared to members of the other group who read printed Academy of Sciences b(PNAS).


books. Even more striking, their body internal clock is shifted by a half hour needed to sleep. In the morning, they need more time to feel fully awake. 

Chronic Insomnia, Breast Cancer and Prostate Cancer 


Screens of computer, smart phones or backlit e-readers have in common the use of light emitting diodes (LED) which diffuse to the face. Furthermore they show a high light intensity comparing to ordinary lamps; LEDs produce much more blue light, leading to chronic insomnia. However, present in the natural light, perceived through the lens of the eyes, it enables the body to regulate the internal clock, also called circadian rhythm, a 24-hour cycle that tells the body when to sleep and regulates many other physiological functions.


The scientists behind the study thus summarize, "These results indicate that reading on this type of reading light in the hours before bedtime has unintended biological effects that can have a negative impact on performance, health and safety." Not only lack of sleep can affect the quality of sleep and alertness, but it can also lead to other health problems such as obesity, diabetes, and cardiovascular disease, as well as different types of cancer.


In various other studies, it has been demonstrated that a chronic decrease in melatonin secretion increases the risk of developing breast cancer and prostate cancer. Previous studies have also found a negative impact on cardiovascular functions, memory and metabolism. In fact, some recent studies have found that people who work night shifts may be at increased risk for cancer, which could be linked to melatonin levels in the body.


The Solution  


Some researchers believe that the solution is to avoid screen of those electronic devices during bedtime but read printed book which increase melatonin secretion and improve sleep.




Light-Emitting E-Readers Before Bedtime Can Adversely Impact Sleep - http://www.brighamandwomens.org/about_bwh/publicaffairs/news/pressreleases/PressRelease.aspx?sub=0&PageID=1962  

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