LED lights are taking the lighting market by storm due to their greater longevity and energy efficiency compared to incandescent and fluorescent bulbs. They are now to be found in every application and appliance from our televisions and laptops to our smartphones. However, despite their benefits they can also have a negative impact on our sleeping patterns. Read on to find out more. And check out this article for more information on LED lights and different solar lighting solutions.

What’s the matter with artificial light?

You may know this already, but ALL artificial lighting, including incandescent, halogen and LED bulbs, has an impact on our natural sleeping patterns. You body’s biological clock operates in time with rhythms which are determined, at least in part, by the quantity of light you are exposed to in your environment. This phenomenon is known as the circadian rhythm, which controls the timing of many processes in your body, including metabolism, feeding, brain activity, hormone release, and yes – sleeping. The brain evolved to set your sleep pattern according to when it is light outside and when it is dark, as determined by the sun and the movement of the earth. Light is detected by your retina, which send electro-chemical signals containing this information to the brain. When your brain receives the information that it is beginning to get dark outside, this triggers it to direct the body to produce sleep hormones (such as melatonin), and to reduce your body’s temperature in readiness for sleep. In the morning, on the other hand, the brain detects the increasing light levels in the environment and directs the body to warm up and release hormones (like cortisol) that promote alertness and wakefulness.

As you have probably figured out by now, the invention of artificial lighting – whether that produced by actual lamps, but also light from the screens of your television, laptop or smartphone device – disrupts this entire process. The brain is now registering the presence of light at all times of day, and so doesn’t know any longer just when to prepare your body for sleep. Studies have shown that exposure to room lights through the evening hours suppresses melatonin production in your body by up to 85 per cent.

Where does LED lighting fit into all of this?

When it comes to artificial lighting, the older incandescent and fluorescent bulbs are rapidly giving way to light-emitting diodes (LEDs) due to the far superior energy efficiency and longevity of the latter. LED lights are now used in every lighting application from ordinary task lighting, to the screens of your televisions, tablets and smartphones. The problem with LED lighting when it comes to our already scrambled sleeping rhythms, is that they generate light of predominantly blue wavelengths, which your eyes are far more sensitive to than other wavelengths of light, and which thus tricks your brain into thinking that there is far more light in the environment than there actually is - this in turn causes your body to suppress it’s production of sleep hormones even more than would be the case otherwise. Studies have indeed confirmed that exposure to predominantly blue light reduces melatonin production more than any other sort of light.


Of course it is not possible in a modern society todo without artificial light altogether, and neither do we ant to deprive ourselves of the obvious benefits of LED lighting technology. However, to prevent sleeping problems caused by over-exposure to blue wavelengths of light, try to turn off your LED-containing devices at least an hour before bed time. The more dimly lit your environment in the period before going to sleep, the easier a time your body will have of it when it comes to producing sleep hormones.

And on the other hand – turning on your tablet, television or smartphone first thing in the morning will promote greater wakefulness and help you feel fully alert and on the ball more rapidly than would be the case otherwise. You can even incorporate dimmers and timers into your home lighting, programming them to light up just before you plan to wake up in the morning. Remember, the more blue-wavelength light your body is exposed to, the greater the suppression of sleep hormones like melatonin produced by your body, and the more wakefulness-promoting hormones like cortisol it will release.

The take home message: turn off the LED devices before bed time, and turn them ON first thing in the morning, if you want to fall asleep AND be awake at the right times.