blue light

http://www.telegraphindia.com/1141215/jsp/knowhow/story_3630.jsp

• Clear bedrooms of electronic clutter and blue light. This includes digital alarm clocks, televisions, computers and cell phones.
•  If a night light is needed, use a red bulb.
•  Do not use in-ear earphones at high volume for long periods of time. Do not give them to children.
•  Do not use cell phones when the charge is dying or for hours at a time or if the signal is weak.
•  Let your fingers do the talking. Texting is safer than calling.
•  Do not let toddlers play with cellphones.

My child" (all of two years) said the mother, "is so smart! She knows how to operate the cell phone. She listens to songs. She even works the TV remote."

Other parents bring their children for consultations, complaining about poor school performance, an inability to recall what has been taught in school or revised at home. On enquiry, they appeared to eat their meals in front of the television and some even do their homework there! The television is never switched off, at least not until the last member of the family finally goes to bed. The problem is compounded if there are olders in the house who do not understand why they need to curtail their television viewing for the sake of the children.

The television emits "blue" light with a wavelength of 475 nm when it is on. During the day, this spectrum stimulates the brain. We remain awake, alert and active. At night, in nature there is no light, so our brains are able to wind down and we sleep. Our brains work in a circadian rhythm, an approximately 24-hour regular sleep-wake pattern.

A chemical called melatonin is secreted in the brain during darkness. It helps us sleep and allows the brain to rejuvenate itself. Any light at night disrupts this process. Blue light is particularly disruptive. It can be from televisions, phone chargers, cell phone messages, computer screens and even low wattage energy efficient lighting. Some studies have shown a link between constant exposure to blue light and cancer, especially that of the breast and prostrate.

Also, the images on television are not really free flowing. They are actually rapidly moving "stop and start" static images. The rapid-fire transmission makes it impossible for our brains to process it making the movement appear fluid. Many brain chemicals get depleted during this process, making the brain tired. Children who watch more than an hour of television a day find concentration and mental recall difficult because of this. They also become irritable, adamant and perform poorly in school.

Where would we be without cellphones? Everyone (even children) have them cradled close to their heads. Cell phones and even cordless phones emit radiation. Although no positive correlation has as yet been made with brain cancer, many advisories advocate no cellphone use before the age of 20, no more than 20 minutes at a time continuous usage and no usage in areas where the signal is weak (the phone emits more radiation as it attempts to connect).

Children under the age of two should be kept away from cell phones. Radiation is emitted up to six inches from the phone even when it is off. They should definitely not be encouraged to use it, play games on it or listen to music. The surface of the cell phone is also highly contaminated with disease-causing bacteria. This can result in respiratory and skin infections.

Earphones can damage our ears and cause progressive hearing loss. This is particularly the case of "in-ear" buds. The over the ear headphones are safer. Special earphones are now made for children. These cannot be used above a certain volume.

Dr Gita Mathai is a paediatrician with a family practice at Vellore. Questions on health issues may be emailed to her at yourhealthgm@yahoo.co.in