WHAT’S NEW ABOUT BLUE LIGHT?
Blue light has been around longer than we have – it’s a natural part of sunlight. So why the sudden interest now?
Because blue light has come indoors. Today, blue light is also emitted by electrical and electronic devices such as smartphones, tablets, computers, TVs and even the humble light bulb. The intensity of blue light emitted by screens can reach 80% of the intensity of a blue sky. And the amount of time we spend in front of a screen is increasing rapidly. In Europe it’s already around three hours, while in the USA and Japan it’s currently more than four hours a day. And that’s only an average!
INDOOR BLUE LIGHT IS NOT NATURAL
The peak emission of light from electronic devices is about 470 nm, firmly in the middle of the blue light range (400–500 nm). There is already strong evidence that concentrated light of this wavelength has adverse effects on health. Its effects on the eyes are well documented and include potential retinal damage and digital eye strain. Blue light at the wrong time of day – for example when we take our phones to bed with us, or stay up late in front of the TV – is known to upset our circadian rhythm and disrupt our sleep patterns.
But what does it do to our skin?
LEARNING FROM EXPERIENCE
For many years, scientists underestimated the damage done to our skin by UV rays. Even after it was recognised that UVB rays damage skin, we still believed that UVA rays were harmless. Now, however, there are strong indications they contribute to skin ageing and wrinkling, and may also enhance the development of skin cancers [World Health Organisation].
At DSM we strongly believe we should learn from this experience and avoid the mistakes of the past. DSM scientists have therefore already been taking a very close look at blue light and its activity in skin. This is what we found.
BLUE LIGHT GOES DEEPER
UVB rays cannot penetrate beyond the skin’s surface, the epidermis. UVA rays penetrate further and reach the dermis. But blue light goes deeper, reaching all skin layers.
Using light sources that excluded UV rays, DSM’s scientists were able to show that blue light has the potential to penetrate and damage all skin layers. At the surface it is a major source of oxidative stress through the formation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). It weakens the epidermal barrier and leads to hyperpigmentation. The damage it causes to the extracellular matrix can accelerate the ageing process.
Going deeper, oxidative stress due to blue light was also shown to trigger a process known as protein carbonylation. Carbonylated proteins in the skin lose their ability to function properly.
DSM TAKES TOTAL PROTECTION INTO THE BLUE
Only time will tell what long-term effects new forms of exposure to blue light may have on our health, and in particular on our skin. But why wait until the damage is done?