Blue Light Health Risks

6^th Jul 2016

Light at night prevents good quality sleep and over time can be harmful to health. Over-exposure to blue light from electronics and energy-efficient light bulbs is said to be worse.

Light is made up of electromagnetic radiation which travels in waves and is visible to the human eye. These waves are all different lengths and strengths, shorter waves having high, strong energy and longer waves having lower energy.

Visible light is seen as colours of the rainbow: red, orange, yellow, green, blue, indigo and violet.

Blue light is part of the visible light spectrum. It has a very short wavelength, so it produces a higher amount of energy. It penetrates deeper into the eye than normal light and its cumulative effect can damage the retina. Macular degeneration is said to be worsened by blue light.

Daytime blue light is beneficial, aiding alertness, memory, mental performance and a reduction in fatigue. So it could be said that using, but not over-using, our computers and phones during the day may give us an energy boost and clear thinking. Blue light is used in standard treatment for newborn babies with jaundice, and in treating skin conditions such as acne and psoriasis. It is excellent for treating seasonal affective disorder (SAD).

Blue light is bad news during the evening and at night. It interferes with our circadian rhythm (our biological clock), tricking the body into thinking that it's still daytime. So the body stops producing the hormone melatonin which winds it down ready for sleep, and the result is that we will struggle to sleep well.

Lack of quality sleep can have harmful effects on the body. It elevates blood sugar levels and hinders the body's ability to use insulin, aggravating or causing diabetes 2. It tends to stimulate the appetite and cravings for high-fat, high-carbohydrate foods, possibly leading to weight gain. It can play a role in depression, and cause mental fog, irritability, short temper, low mood, poor judgement, slow reflex reactions and accidents, as well as ageing skin.

Office workers who spend long hours in front of a computer, at work stations lit by strip lighting, with only a short break for lunch, which may or may not be spent outside in daylight, are particularly prone to overdoing the blue light, under-doing essential daylight and heading for poor quality sleep. After work there may be the gym, pub, cinema or shops, all with artificial light. Back home, the evening may include more computer, television, phone and energy-efficient light bulbs, all of which emit blue light.

Then comes bedtime with possibly the phone, ipad, e-reader, bedside lamps, digital clock and other electronics, and if you are unlucky enough to have a street lamp shining into your bedroom all night, you could be heading for sleep disaster and possible illness.

Here are a few ways to enable quality sleep, a strong immune system and a sense of well-being:

Get more daylight
Spend more time in daylight, especially when you work indoors. That lunch break would be better spent on a park bench or walking outside, than in the gym or rushing around the shops. Not only does daylight aid your ability to sleep at night, it will also boost your mood and alertness during the day.

Reduce the electronics at night
Well before bedtime, put away the computer, television, phone, e-reader (a good old-fashioned book is a wonderful idea here) and any other piece of electro equipment that you usually take to bed with you. Replace the digital clock with a battery-operated one. Out with the electric blanket and in with a couple of hot water bottles.

Change colour
Use dim red or amber lighting for night lights, such as digital clocks. Red has the longest wave length and the weakest strength. Amber is second best.

Use candles
Using artificial light in the evening before bedtime shuts down melatonin production, so when you have finished doing all the essentials that need good light, use candles.

Wear blue-blocking glasses
If you really cannot reduce your night-time exposure to blue light, try a pair of blue-blocking glasses.

Enjoy a relaxing bath
If you're going to make an effort to reduce the electronics and get healthy, and you are wondering what to do with the extra time normally taken up with all this equipment, run a hot bath and relax into it. There's nothing better for calming and soothing ready for a good night's sleep.