With the ongoing COVID-19 pandemic, staying home all day through is becoming the increasing norm. Without the sunny outdoors, it intuitively feels like ultraviolet skin damage is not possible. Should we then tone down on our daily skincare? How about windows and computer screens? We ask these questions to our resident dermatologist here at Singapore, Dr Teo Wan Lin, to find out more!
Is ultraviolet skin damage from the sun possible if I sit near a window with day curtains?
Definitely, ultraviolet rays will penetrate through the window panes. That is, unless there is a special ultraviolet filter on the window pane to eliminate solar rays. Hence, my advice is to please continue wearing your sunscreen even when you are indoors. To believe that you are not getting the harmful ultraviolet-A and ultraviolet-B rays (that causes skin-aging and skin-burning respectively) at all when you are indoors, is simply not true.
Day curtains certainly do provide some sort of ultraviolet protection factor. They are however by no means acceptable in terms of replacing your sunscreen. Sunscreen comprises 2 types of coverage. Firstly, we have the broad spectrum factor. This refers to the ability of the sunscreen to block out ultraviolet-A and ultraviolet-B radiation. The other factor would be what we call the SunProtection Factor or SPF. This measures the amount of sunscreen that helps to reduce the likelihood of your skin getting sunburn.
In practice, if a sunscreen has an SPF of 30, it means that when you apply the sunscreen, you are 30 times less likely to burn. Accordingly, if its of SPF 50, it will be 50 times less likely to burn within the same timeframe that you are under ultraviolet light. Now, when it comes to the types of curtain, there are those which are more tightly woven. These are as opposed to day curtains which do let some light in. Fabrics which are very tightly weaved would certainly achieve the function of blocking out ultraviolet. However, these types of curtains are almost definitely the black out types. It then becomes kind of counterintuitive, because you do want to let some light in during the daytime.
From a dermatologist’s perspective, can looking at a computer/TV/phone screen for extended periods of time cause ultraviolet skin damage?
Most devices these days do not emit ultraviolet radiation. This is except for perhaps the old CRT monitors which certainly have a role to play in ultraviolet skin damage. The CRT technology is however obsolete. Any device with an LCD or more advanced display technology would not emit ultraviolet. So the question here really is whether visible light, especially the blue light component, emitting from common devices is harmful for skin.
There was a landmark study done some years ago showing that the blue light component emitted by devices can actually worsen underlying pigmentation. This is more specific to those people who already have skin pigmentation issues. In particular, there is a rather disfiguring condition known as melasma. Melasma often manifests as a butterfly shaped distribution of pigmentation that lies pretty deep in the skin. Therefore, if you have melasma or say sun spots (also known as solar lentigo), do take precautions. In this case, if there are sources of blue light (e.g. computers, LED lights, smartphone) in your home, then definitely I think it helps to reduce your exposure to them.
How about the rest of us?
Notably, we are not sure if it is realistic to try to block out all source of blue light. First of all, for normal people who do not have underlying pigmentation issues, the effects of these blue light devices on the ageing process is not very well proven. It is also quite indispensable in a sense that blue light can come from many common household appliances, although mostly at low intensities.
Unless you have a very significant source of blue light, such as a home-use blue light therapy device, which some may try to use for acne treatment. Bearing in mind, dermatologists would only prescribe supervised in-clinic blue-light treatments, rather than recommend home therapy. Practically, in avoiding blue light sources, I think it would make sense to do this when we’re sleeping. This is due to the long hours where there is no need for any use of devices. Other than that, in our day to day exposure, I do not think it is possible to eliminate sources of blue light.
What else can we do?
What will help in the broad scheme of things is to use dermatologist tested sunscreen and antioxidant skincare. Other than looking for the dermatologist label, you can also look towards botanical plant extracts, besides the usual vitamin c. For example, we have portulaca oleracea and centella asiatica. These are bioactive plant derivatives that help to fight free radical damage, which our cosmeceuticals, such as the SunProtector and Elixir-V Serum, use in their formulations.
The significance of blue light emitted from common devices, affecting the skin and the aging process, needs to be studied further in detail for us to make a definitive stand. Nevertheless, why not take a preventive step anyway with cosmeceutical skincare. This is because with or without blue light exposure, there is photo-aging with ultraviolet skin damage from the sun. Do bear in mind that one of the strongest sources of blue light exposure is actually together with ultraviolet light in solar radiation that we experience everyday, even indoors by the windows.