How Blocking Blue Light At Night Can Improve Your Sleep

by Dr. Jonathan D'Souza


A healthy, uninterrupted sleep is just as important as breathing or eating. And if sleep has been eluding you lately, you aren't alone.Insomnia, or sleeplessness, is a common complaint these days, the fall-outs of a stressful lifestyle. Poor sleep can lead to heart disease, depression, and type 2 diabetes and is one of the biggest risk factors for obesity.[1,2,3,4]

While we have been sleeping much lesser than our predecessors, our quality of sleep has suffered as well. The single largest contributor to our sleeping woes is the use of electronic devices such as cell phones, tablets, laptops, computers and LED televisions.

These devices give out light of blue wavelengths that makes the brain think that it's daytime.[5] Research suggests that blue light in the evening disrupts the brain's natural sleep-wake cycles, which is essential for the optimal function of the body.[6,7]

How Blue Light Impacts The Brain

Our body has an internal clock, also known as the circadian rhythm, a 24-hour biological cycle situated in the brain that influences various internal body functions.[8] It determines how wakeful you feel during the day and when you are tired and want to doze off.[9]Blue light stimulates the receptors in the eyes, which send signals to the brain's internal clock.

White light (sunlight) contains a mixture of various wavelengths (including blue wavelength).[10] Getting sunlight (that contains blue light) during daytime is important, as it improves performance and mood.[11] In fact, blue light devices can treat depression and blue light bulbs at offices can reduce fatigue, improve productivity and sleep of workers.[12,13,14]

However, at night, blue light can prove to be a disaster. Modern devices, especially cell phones and tablets, produce blue light that tricks the brain into thinking it's daytime. As the day comes to an end, the pineal gland in the brain secretes the hormone melatonin (known as the sleep hormone), which sends out a signal to the body and the brain that it's time to fall asleep. Blue light is effective in inhibiting melatonin production.[15,16] Melatonin suppression in the evenings can cause various health problems such as metabolic syndrome, obesity, and psychological disorders such as depression.[17,18,19,20]

Simple Ways To Block Blue Light At Home

Follow these simple tips toreduce your exposure to blue light and improve sleep quality.

1. Use blue light blocking glasses while using electronic devices at night. Clinical studies show that people using blue light blocking glasses in a lit room or while using an electronic devices produced the same amount of melatonin as in the dark.[21,22] A study showed that blue light blocking lenses improved sleep and reduced daytime dysfunction in elderly patients with cataract.[23]

2. Switch off all the lights in your home one to two hours before bedtime.

3. Keep your bedroom completely dark when you sleep. You can also use a sleep mask to block light out.

4. If you work late nights, avoid using blue lights and get a red or orange reading lamp.

5. If you work on the computer at night, consider downloading a free software called f.lux. This software adjusts the color and brightness of the screen according to the time zone, minimizing the blue light emitted. Click hereto download it.

Image Source: Shutterstock

For more interesting stories, visit our Health page. Read more about Diseases & Conditions here.

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Natural Remedies For Better Sleep During Pregnancy


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12. Sanassi LA. Seasonal affective disorder: is there light at the end of the tunnel? JAAPA. 2014 Feb;27(2):18-22;quiz 23. doi: 10.1097/01.JAA.0000442698.03223.f3. PubMed PMID: 24394440.

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15. Gooley JJ, Chamberlain K, Smith KA, et al. Exposure to Room Light before Bedtime Suppresses Melatonin Onset and Shortens Melatonin Duration in Humans. The Journal of Clinical Endocrinology and Metabolism. 2011;96(3):E463-E472. doi:10.1210/jc.2010-2098.

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