Ultraviolet A and B have long been recognized to be responsible for premature skin ageing, pigmentation and skin cancers. More recently, blue light has been found to play a role too.
Blue light is in the spectrum of visible light. It has high energy and a short wavelength. It penetrates more deeply into the skin than ultraviolet A and B, causing damage in the part of the skin where collagen and elastin are located. Blue light may also stimulate the production of free radicals in theskin. The results of excessive blue light exposure are premature skin ageing like winkles, skin laxity and pigmentary problems like melasma. The damage occurs over time and hence the effects may not be immediately visible.
Apart from harming the skin, blue light can also cause strain to the eyes, cataracts, glaucoma and retinal degeneration.
The main source of blue light is the sun. The other sources are computer monitors, mobile telephones, LED and fluorescent lights. Spending four regular eight-hour work days in front of the computer exposes one to the same amount of energy as twenty minutes in the mid-day sun.
One of the ways to protect ourselves from the harmful effects of blue light on our skin is to use a broad spectrum sunscreen that blocks blue light. Most sunscreen products specify the level of ultraviolet A and B protection. For effective blue light protection, the sun screen needs to provide a physical barrier and the blue light protection factor should be 35% and above.
Dimming the brightness of the computer screen and using your device in the “night mode” may also be helpful.
The Covid-19 pandemic has resulted in many people working from home and spending large amounts of time in online meetings and so on. We should be aware that we are substantially increasing our exposure to blue light due to the long periods of time spent in front of the computer monitor, thereby subjecting ourselves to premature skin ageing and pigmentation. It is unclear how much screen time is considered “safe”. It would be prudent to use a blue light protecting skin product, especially since many of us would continue to work from home for the foreseeable future.
As we practise social distancing to prevent the spread of Covid-19, we should also consider distancing ourselves from our blue light emitting devices to minimize the damage to our skin!
(The author is a consultant dermatologist at Mount Elizabeth Novena Hospital)
This article was first published on Lianhe Zaobao and the English version published on our website with permission.