When it comes to sun protection, we've (thankfully) come a long way from the days when it was the norm to oil and sunbathe, or jump into a tanning bed to polish up a skin tone bathed in Sun.
But despite the general increase in knowledge of the sun, there are still some blind spots. One of them is the mistaken belief that sunscreen can be given up when we are indoors.
Ultraviolet radiation from the sun can penetrate most windows in homes and cars. That is, even if you are behind closed doors, light rays can damage your skin.
And if the coronavirus pandemic has you working from home, you are likely to spend more time indoors than if you were on the way to the office or to your workplace.
But what really happens if you skip the SPF dose when you're indoors? Does it really have that much of an effect on your health and appearance?
Is there sun protection while at home?
There are two types of ultraviolet radiation: UVA and UVB rays . Each of them penetrates different levels of the skin and affects different structures of the skin.
UVB rays are directed at the surface layers of the skin. They damage the DNA in the skin, are the leading cause of sunburn, and cause most skin cancers.
However, a September 2009 study published in Photo-Immunology Photodermatology and Photomedicine revealed that window glass filters out deadly UVB rays.
Still, windows are not very effective at blocking UVA rays, which penetrate the deeper layers of the skin. The same study determined that 74 percent of UVA rays are transmitted through glass. UVA radiation is responsible not only for skin cancers but also for the breakdown of collagen that results in photoaging.
These rays penetrate the dermis, damage collagen and elastin, and trigger accelerated aging. Think sagging, wrinkles, leathery skin, and hyperpigmentation.
LED and blue light is also a problem for the skin
It is not just the sunlight that poses a danger to your skin. Blue light from LED ceiling lights and electronic devices (like your phone, laptop, and television) can also wreak havoc.
It penetrates the skin, increasing the generation of free radicals, which break down collagen and elastin, leading to premature aging.
A December 2018 study published in the Journal of Biomedical Physics & Engineering indicates that as little as one hour of exposure to blue light can damage the skin.
The bottom line is that just because you stay indoors doesn't mean you don't have to wear sunscreen, and you should apply it to all bare skin, rather than just your face. Put it on your face, ears, neck, chest and arms, if they are exposed. Apply just enough to create a film on your skin that you have to rub in.
The type of sunscreen you use is important, so this is what to look for. Use a broad spectrum sunscreen with an SPF of at least 30, that blocks UVB and UVA rays and offers partial coverage against blue light. Sunscreens that contain iron oxide provide more complete protection against blue light and are therefore recommended for people with hyperpigmentation disorders such as solar lentigines or melasma.
Is it bad not to use sunscreen indoors?
There are experts who believe that it is moderately bad, but not terrible.
Based on what we now know, light from electronic screens and UVA radiation through the window can have an effect on the skin. Wearing sunscreen indoors is quite important to staying safe and skin cancer-free, especially these days where people spend more time in home offices and don't venture out as often.
That is, on a risk scale of 1 to 10, where 10 is sunbathing on a scorching day with no SPF, and 1 is not using sunscreen in the middle of the night, experts say not putting on sunscreen indoors is a 4 or 5.
