Blue Light…What’s the controversy?

There seems to be much talk about blue light and its effect on the visual system and our bodies these days. Subsequently, multiple blue blocking vision products have appeared on the market making various claims to benefit the user.

What do I need to know about blue light and these products?

In order to understand blue light better, we need to get a bit technical. Each colour has its own wavelength of light. Putting all the colours together gives rise to the visual spectrum (ROYGBV). Light that we see with our eyes usually consists of a combination of these wavelengths. For example, white light consists of the entire visual spectrum.

Blue Light and Vision

Blue light consists of short wavelength energy as opposed to red light which is long wavelength energy. This short wavelength light has the potential to decrease quality of vision in two ways. First, short wavelength light tends to scatter more than longer wavelength light. Second, short wavelength light tends to focus just before the retina causing a slight decrease in sharpness of this image.

Blue blocking vision productscause an increase sharpness by eliminating scatter from blue light as well as decreasing the blue component of light that is not focused on the retina when we are viewing an object.

Sign me up… right?

Blue light and our Bodies

Well, nature is not black and white….or in this case blue and yellow. It turns out that blue light is very important to our bodies for more than just vision. Blue light stimulates specific centres of the brain responsible to help regulate circadian rhythms, neurotransmitter and hormone production. Blue light during the daytime contributes to many important background functions that helps us function optimally. Conversely, increased exposure to blue light at night can decrease melatonin production which is the hormone responsible for helping one sleep.

Gets complicated doesn’t it?

In part II of this blog, I will discuss some of the products on the market and why they may or may not be beneficial to our day to day activities.