'ब्लू लाइट' दिन में अच्छी और रात को बुरी Blue Light Good or Bad For Health

Author : Dr. P. D.GUPTA

(Former Director Grade Scientist, Centre for Cellular and Molecular Biology, Hyderabad, India)


Great Indian Scientist Sir C V Raman who was awarded Nobel Prize in Physics for the first time showed that sun light is composed of 7 colours called VIBGYOR ((Violet–Indigo–Blue–Green–Yellow–Orange–Red); pretty much like we see in the rainbow. The conclusion drawn here is that sunlight is nothing but a mixture of seven colors. And these seven colors combine to form the white light.   

Light is like salt and sugar we cannot live without them but if we take them too much they affect our health adversely; too much can cause several kinds of serious health issues. But small amounts, especially early in the day before it’s at its brightest, can be good for you in some ways. 

We need sun light over your lifetime, for seeing things at a distance (through our eyes). But too much direct sunlight can hurt your eyes. It can lead to blurred vision and raise chances of developing cataracts.    

The colours are arranged in vibgyor according to the  wave-length of the light (colours) , violet being shortest  to red longest.  Short wave length light has more penetrating power in the body whereas red light cannot penetrate the body.   

Now a day’s viewing gadgets (TV, mobile phones, computers, etc. ) emit blue light and this is also having short wave length. We are now more exposed to blue light and therefore discusing good and bad effects of blue light.  

Day time 

Blue light is supposedly beneficial during daylight hours because they boost attention, reaction times, and mood. However, these lights are great for the daytime because they keep us awake. Blue light is needed for good health: It boosts alertness, helps memory and cognitive function and elevates mood. It regulates circadian rhythm – the body's natural wake and sleep cycle. Exposure to blue light during daytime hours helps maintain a healthful circadian rhythm.  

Night time 

Unfortunately most of us and especially teens and young adluts work on computers, mobile telephoes and  grownups and elderly people watch TV during night hours get bad affects of blue light. This high energy blue light passes through the cornea and lens to the retina causing diseases such as dry eye, cataract, age-related macular degeneration, even stimulating the brain, inhibiting melatonin secretion, and enhancing adrenocortical hormone production, which will destroy the hormonal balance and directly . 

More so than any other color, blue light messes with your body's ability to prepare for sleep because it blocks a hormone called melatonin that makes you sleepy.  It means You're less drowsy than usual at night, and it takes you longer to fall asleep. .Since blue light keep us awake during day time, and bad at night because they often impede sleep.  

Researchers measured contact to outdoor and indoor artificial light and found blue light exposure doubled a man's risk of prostate cancer and increased a woman's chances of developing breast cancer by 50 percent.  

Minimize the Damage caused by Blue light  

Here are a few steps to follow: 

Maintain a safe distance. ... 

Try the “20-20-20” rule. ... 

Restrict the use of devices at night. ... 

Use artificial tears. ... 

Adjust the computer brightness and contrast. 

Adjust lightings near your device. 

Consider using a matte screen filter for your electronic device.

(The author has his own study and views)