In the southern hemisphere here in New Zealand we are just over mid way through autumn with our winter solstice looking to be on the 21st June which always seems to come around quite quickly. This is often the marker into the downhill glide into summer, however we have the dark nights and mornings to deal with until the clocks go forward.
So, with winter, we all know that there is less sunlight as it tracks lower across the sky and temperatures drop with the reduction in ultra violet light radiation. Over these next few months we change our habits in dealing with the change in sunlight and so now is the time we should be paying special attention to the light environments we expose ourselves to.
If we look at some of these, in particular with indoor lighting, we tend to put house lights on sooner in the day and leave them on longer, and if your house is designed with lowered natural light coming in, you maybe more likely to turn lights on more often including first thing in the morning. Lighting has now moved from the good old incandescent bulb to the energy efficient LED bulbs and with it, a marked increase in blue light. If we look at the light spectrum of an LED bulb there is little to no red light. Red light is heat and uses up energy and we know LED bulbs remain cool to the touch. So now the light from these bulbs is predominately made up of the blue spectrum.
Spending more time indoors we also spend more time in front of devices and other screens which also have high levels of blue light for the same reasons above. Now these levels of blue light are outside the normal range of what we would see from the sun and what we calibrate ourselves to, hence the issue.
To look at this from another angle that adds to our blue light loading, the windows in modern houses use glass which block parts of the light spectrum covering UV and some red light, but not the blue. The shorter blue wavelength passes through unencumbered. Why is this relevant? This means we have more unbalanced blue light coming into the home. In nature, outside in the sun, all light is balanced throughout the day with the dominant light which is red and the changing UV light. Take these away and you increase blue light exposure. This is an important point to raise, the glass we rely on in our homes adds to our blue light exposures, by blocking or reducing the complimentary colours.
All this boils down to one thing, unbalanced blue light at the wrong times of day. I will expand on this in future blogs, but know that blue light is central to our circadian clocks and how we relate to the time of day plus a huge amount of other biological interactions that are paramount to our health. Some of which is already covered on the page “What is blue light?”. Blue light from the sun changes from about 19% to 26% of the total light spectrum from winter to summer and also increases throughout a normal day from sunrise to sunset.
So knowing we have an issue with our light environment means that our control of this comes from two things, either turning lights off and blocking the blue with glasses. Wearing Rama glasses when indoor lighting is present or when using devices gives us the ability to lower and block blue light when giving us the control over the environment we have created for ourselves, including our work places. Remember that blue light at night is a stimulating light and will reduce your ability to have a good nights sleep. Conversely, blue light first thing in the morning will fast forward your body clock to around solar noon.
Our BluePeak daytime yellow lens and SleepWell night time lens offer a choice of protection depending on your situation throughout the day. This modern life we have created has taken us further and further away from nature, and for that, we need to do extraordinary things to get back on track. Learning about blue light is one of those extraordinary things.