We all know that staring at screens for hours is making us stupid, damaging our eyesight, ruining our sleep patterns, shortening our concentration spans and probably killing us. But here’s some news that might make even the most ardent selfie-taker throw their phone in the sea – all that blue light from our screens might be making us look older.
What is blue light?
Sunlight contains red, orange, yellow, green and blue light rays and many shades of each of these colors, depending on the energy and wavelength of the individual rays (also called electromagnetic radiation). Combined, this spectrum of colored light rays creates what we call „white light” or sunlight.
Blue light refers to light wavelengths between 390 and 500 nm.
Those who have looked into information about blue light have probably come across the term HEV, which stands for High Energy Visible light or in other words light containing a high dose of energy.
Without getting into complicated physics, there is an inverse relationship between the wavelength of light rays and the amount of energy they contain. Light rays that have relatively long wavelenths contain less energy, and those with short wavelengths have more energy.
Rays on the red end of the visible light spectrum have longer wavelengths and, therefore, less energy. Rays on the blue end of the spectrum have shorter wavelengths and more energy.
Blue light rays are sometimes called blue-violet or violet light. This is why the invisible electromagnetic rays yust beyond the visible light spectrum are called ultraviolet (UV) radiation.
HEV light rays make the sky look blue
The short-wavelength, high-energy light rays on the blue end of the visible spectrum scatter more easily than other visible light rays when they strike air and water molecules in the atmosphere. The higher degree of scattering of these rays is what makes a cloudless sky look blue.
Blue light is everywhere
Sunlight is the main source of blue light, and being outdoors during daylight is where most of us get most of our exposure to it. But there are also many man-made, indoor sources of blue light, including fluorescent and LED lighting and flat-screen televisions. Most notably, the display screens of computers, electronic notebooks, smartphones and other digital devices emit significant amounts of blue light. The amount of HEV light these devices emit is only a fraction of that emitted by the sun. But the amount of time people spend using these devices and the proximity of these screens to the user’s face have helath care professionals concerned about possible long-term effects of blue light on health.
Is blue light harmful?
The HEV light can penetrate deep into your skin. The question then is: how harmful is this?
There are studies which show that exposure to a high dose of blue light can cause the generation of free radicals. And, just like the free radicals which arise through exposure to UV radiation and pollution, this can eventually cause wrinkles and pigmentation spots. But delving a little deeper into these studies, we can notice something significant. Special lamps with a high dose of blue light were used in these tests. In fact, this dose cannot be compared to the amount we get in normal everyday life.
There is, furthermore, another significant point. No relationship between exposure to blue light and skin cancer was found from the studies. The DNA damage which occurs through UVA and UVB radiation is not apparent in exposure to blue light.
Blue light can also weaken the epidermal barrier and delays barrier recovery.
Not all blue light is bad
It’s well documented that some blue light exposure is essential for good health. Research has shown that high-energy visible light boosts alertness, helps memory and cognitive function and elevates mood.
In fact light therapy is used to treat a type of depression that’s related to changes in seasons, with symptoms usually beginning in the fall and continuing through winter. The light sources for this therapy emit bright white light that contains a significant amount of HEV blue light rays.
Also, blue light is very important in regulating circadian rhythm – the body’s natural wakefulness and sleep cycle. Exposure to blue light during daytime helps maintain a healthful circadian rhythm. But too much blue light late at night (reading a novel on a tablet computer at bedtime, for example) can disrupt this cycle, potentially causing sleepless nights and daytime fatigue.
This part of solar spectrum also strengthens the immune systemand have an antibacterial effect. This is why lamps whith blue light have been used to treat acne for a long time.
A recent study even showed that blue light has an advantageous effect on veins and arteries and can lowes blood pressure.
No filters for creams to block blue light
The cosmetics industry wouldn’t be the cosmetics industry, though, if it hadn’t found a solution for this; special blue light creams and serums to protect us against so-called screen face.
The above mentioned leads to the logical conclusion that it is not wise to block out blue light completely. If you were to do that, then you wouldn’t really know what the negative effects are. There aren’t actually any filters which can do this; there is no such thing as a special blue light filter for creams.
Filters that can block out a small portion of the blue light are zinc oxide, titanium oxide and Tinosorb M; all other sun filters have no effect on blue light. Another piece of information for you is that iron oxide, used in foundations and powders, can also block out a portion of the blue light. It is indeed useful to reduce the free radical damage which occurs through light. There are, however, no special antioxidants for this; in fact all the usual antioxidants, such as vitamin C, B3 (niacinamide) and E plus many more, are very suitable for this.
Less time spent behind the screen is a good idea
Since it has been proven that too much blue light is not so good for our sleeping pattern, we should spend less time behind computer or telephone screens, especially in the evenings. That will also benefit in another way, as a good night’s sleep, sufficient relaxation and minimal stress work wonders for your skin.