Blue Light And Its Adverse Effects

Blue Light

What Is Blue Light?

In the white light, seven other lights make up the white light. The visible spectrum of light contains the different wavelengths of light which can be perceived by the normal human eyes. This visible spectrum of the light consists of blue light and has a very short wavelength but has the highest energy among the other lights. The sun is considered as the main source of light and it has a wide spectrum of colored lights which a human eye sees as white light.

Blue Light


All the colored light has a different energy and different wavelengths. The warmer colors have long wavelengths and less energy whereas, the cooler colors have short wavelengths and high energy. The white light radiated from different screens usually has a higher amount of blue light than any other light of the spectrum. The amount of exposure to blue light from the sun is more than the screens but blue light exposure from screens is more concerning than the sun due to the close proximity of screens to us. The increased use of screens has made us sit in front of them for a longer duration of time making us vulnerable to the harmful effects of the blue light. Blue light is considered harmful as well.

Sources of Blue Light

Sources of Blue Light


Blue light is radiated from any source that emits white light. Sun is considered as the natural source of it and radiates a high amount of blue light. The screens that we use including our phones, laptops, computer, tablets, and LED television screens all to radiate blue light. The fluorescent lighting in our house including the CFL bulbs and the LED light is also the source of it.

The lights in our house are energy- efficient but the incandescent bulbs that we used earlier didn’t radiate the blue light and had fewer effects on our health. It gets radiated from these sources and is more harmful than the blue light radiated from the sun. This is so because the proximity of the screens to us is less as compared to the proximity of the sun and us.

Health Benefits of Blue Light

Health Benefits of Blue Light


Blue light is known for its adverse effects on our health but is also necessary for maintaining good well-being.

  • It is necessary for the growth and development of eyesight in children as the sunlight helps in improving their vision.
  •  It is also known to boost alertness and increases the memory of a person.
  •  It also boosts the cognitive function of the brain as well as helps in elevating your mood.
  • It also helps in regulating the natural sleep and wake cycle which is known as the circadian rhythm. In the daytime exposure to blue light helps in maintaining a healthy circadian rhythm but exposure to light at night time disturbs the normal healthy sleep and wake cycle of the body.
radiation from sun


  • The radiations from the sun stimulate and boost our energy in our daytime and make us feel sleepy at night time.

Experts have suggested that sleeping in dark rooms and an absence of blue light should be necessary for a proper night’s sleep. A study has also shown that deficiency in exposure to blue light radiated from sunlight can lead to myopia and improper development in children.



Adverse Effects of Blue Light

It has more harmful effects on health. Increase use of screen time has led to a decrease in the health of the individuals.

Adverse Effects


Having an eye strain is very common among people who use screens for long intervals of time. The amount of blue light being radiated from the screens is more and it leads to a reduction in the contrast sensitivity of the eyes causing eye strain. It has also been noted that people tend to blink less when they are occupied in their work on the screen which causes dry eyes and irritation in the eyes. There has been an increase in headaches, blurred vision, neck pain and shoulder pain of the people who have to sit in front of the screen for a long interval of time.

It can easily pass the cornea of the eyes as human eyes are not capable of blocking the harmful rays from blue light. Continuous exposure of it for a longer duration of time leads to degeneration of the retinal cells as it penetrates from the cornea of the eyes and strikes against the retina causing damage to the retinal cells. This leads to age-related macular degenerationcataracts, eye cancer, and many other eye problems contribute due to long exposure to blue light. Macular degeneration affects females more than males. The other risk factors that contribute to AMD are smoking, diet, genetics, and light iris coloration.

danger from retina


Even slight exposure to blue light at night time disrupts the sleep pattern and has led to various other ailments. Exposure to blue light at night time leads to shifting of circadian rhythm, lower levels of leptin hormone, and suppression of melatonin hormone. Lower levels of leptin hormone make people feel hungry even after they have had a proper dinner (night cravings). The suppression of melatonin affects the circadian rhythm as the hormone is responsible for its proper regulation. People who have a short night’s sleep increase their chances of contracting diseases like diabetes and cardiovascular diseases.

LED blue lights though are environment friendly and have contributed to being the energy-efficient light source but, they cause personal health problems as they tend to produce lighter when compared to the incandescent bulbs that were earlier used. The coatings can be introduced inside the bulbs and fluorescent lights to reduce the emission of blue light from them.

How To Protect The Eye From Blue Light?

As there has been an increase in the amount of work and duration of hours that one spends in front of the screen, we cannot completely remove the use of screens from our life. To maintain our health, we need to take some precautions in order to protect our eyesight from blue light.


Investing in good computer eyeglasses is the best way to protect eyes from blue light. The computer glasses have a particular coating present on the top of the lenses which blocks the blue light from reaching the cornea of the eyes. It helps in reducing the digital eye strain caused due to working on screens for long hours. If you have work on a laptop or computer and need to sit in front of them for long hours then it is advised to purchase good quality computer glasses. You can also ask the optician to add an anti-reflective coat on the lenses to protect from blue light from both sides of the lens.



If investing in computer glasses is costing you a fortune then the cheaper option is to get a protective covering on the devices. The protective covering is a screen filter that limits exposure to blue light. They are generally inexpensive and absorb blue light radiated from the devices, reducing the eye strain from the eyes. Installation of apps on the device that filters the blue and green light at night can also be beneficial in controlling radiation exposure.

Eye Exercise

It is beneficial in taking a break after every 20 minutes of work. The 20-20-20 rule is the ideal rule to follow to reduce the eye strain, dry eyes, and red eyes caused due to long exposure to the blue light of the screen. The rule states that you should take a break of 20seconds to view an object placed 20 feet away after every twenty minutes. This has been very helpful in reducing eye strain. 

Eye Exercise



The Intraocular lens also protects from blue light as they block the radiations that reach the eyes and protect the retina from getting damaged. Intraocular lenses usually are prescribed to people who have undergone cataract surgery as they need protection from ultraviolet radiation.

Dim Lights

The use of dim lights at night can help in maintaining the supply of melatonin and would not shift your circadian rhythm. Instead of using bright table lamps by the bedside replace them with table lamps with red light. During the daytime expose yourself to sunlight as it will boost your alertness and will elevate your mood. It will also help you to boost your ability to sleep during the nighttime.

Dim lights


Avoid using electronic gadgets and television screens two to three hours before bedtime. As it will maintain your natural sleep-wake cycle.

Healthy Diet

Healthy Diet


Maintaining a proper healthy diet is also a key to healthy eyes. Drink plenty of water and blink continuously to maintain the moisture in your eyes. Take certain minerals and vitamins which are important for the health of the eyes. Nutrients like carotenoids, lycopene, anthocyanosides , flavonoids, beta carotene, and vitamin A, E, and B complex help in improving the health of the eyes. A daily dose of multivitamins and mineral supplements can help in filling out the nutritional gap in the diet you take. Consultation from a doctor is required before you take any kind of supplements.

Certain lifestyle changes and taking a proper diet can help in reducing the chances of getting eye problems and will relieve you from getting eye strain and headaches. Before getting computer glasses it is advised to visit an ophthalmologist so that a proper eye exam can be done. If there are any changes in the vision then it is advised to visit the doctor immediately.

The best way to treat your eyes is to visit your eye care professional and get your eyes checked regularly. He will be able to assess the best method of treatment for your eye ailment. Visit our website Eyemantra. To book an appointment call +91-9711115191. Or mail us at [email protected]Our other services include Retina SurgerySpecs RemovalCataract Surgery, and many more.

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