Should You Wear SPF Inside? This Is What The Experts Reckon

Javier Díez / Stocksy

Most people know just how important wearing SPF on our face is these days. Scientists and beauty experts alike will tell you that the best thing you can do to safe guard your skin for the future is to wear sunscreen in order to protect it. And while it's advisable to wear it year-round (not just when it's sunny), it may also be a good idea to wear it even when you're not outdoors. So should you wear SPF inside? Let's discuss.

Although the sun can help some of us feel happier and more social, it can be a nightmare for our skin. Damaging UVA and UVB rays can cause irreparable damage and can even lead to skin cancer, as the American Academy of Dermatology notes. On a purely aesthetic level, as HuffPost reports, sun damage can dry out the skin, cause pigmentation and uneven skin tone, and can destroy the collagen and elastin in your skin. This in turn leads to a loss of elasticity and firmness; in other words, pre-mature ageing. Wearing SPF in part protects us from these side effects, and hence should be taken really rather seriously.

Alarmingly, according to the Independent, approximately 80 per cent of UV rays can still penetrate through clouds, meaning SPF is crucial even in colder months, and should be worn year round. But if UV rays can penetrate through clouds, can they penetrate through, say, the glass of our windows? If so, would that suggest we should be applying SPF even on days we may not be leaving the house?

Facialist and skincare expert Lisa Franklin believes it's better to be on the safe side with this one. "Glass effectively blocks UVB (the UV rays that cause sunburn), but about 75% of UVA penetrates glass," she explains.

"UVA rays are the UV wavelength that lead to skin damage, ageing and can eventually lead to cancer. So, while you won’t get sunburn through glass, our skin is still very susceptible to damage."

Tracey Beeby, Head of Global Training for Ultraceuticals also echoed these views when she told The Huffington Post Australia:

"UVA rays can also penetrate through glass, so even travelling to and from work, walking from your car to the office, sitting by a window, taking a lunch break outside, putting the clothes out on the line; all these times expose us to these damaging UV rays of which accumulate over the day."

As well as the rays from outside, Franklin also warns that blue light from your phone or laptop can also have the potential to damage skin while indoors. "All of my clients are now seeing skin concerns that have arisen from too much screen time," she says.

"Research behind this is now becoming more available, and several studies now show that skin exposed to blue light suffers from biological alterations. There is also evidence to show that exposure causes a massive increase in free radical production and pro inflammatory cytokines."

In short, blue light can be potentially harmful too. For these reasons, Franklin recommends applying an SPF whether you are leaving the house or not, to be safe:

"As a general rule [I say]: if it’s light enough to see, then wear SPF!"

She recommends using a moisturiser that offers protection against blue light (such as her Pro Effect Pollution Defence Cream), as well as an SPF, so you are safe from all three.

If you're keen to pick up a brilliant face SPF, I recommend trying the Ren Clean Screen Mineral SPF 30, the Glossier Invisible Shield (SPF 30), or the Aesop protective Facial Lotion SPF 25; all of which are my faves.