If I had a dollar for every time I was asked IF and WHY we need to wear sunscreen indoors, or in winter, or when it’s cloudy, I’d be able to afford Meredith Dairy Goats Feta in my weekly shop. The large jar. 

I’m soooo sick of answering this question. SO, instead I asked Ava Matthews, co-founder of Ultra Violette and sunscreen aficionado, to do the explaining. 

Here’s a transcript of our conversation. 

Watch: What's actually happening to your skin when you tan. Post continues below.

Do I need to wear sunscreen inside?

“Well… A bit of context is required. Are you inside near a window? Do you leave the house at any point during the day (coffee breaks, to take a phone call outside, eat a snack on your balcony, to walk to get your lunch, sit in the car and scream etc. etc.)? 

If the answer to any of the above is yes, then you need to wear SPF.

“If you literally sit inside all day every day from 8am to 5pm and you don’t have any windows and don’t leave the house then you’d probably be fine to go without. If that is the case, SPF application probably isn’t your biggest problem. Check yo vitamin D levels!!”

Okay so I don’t sit in a dark room all day, so that means I need it. But why?

“Because you’re still getting some exposure. Pending the time of year, how close to windows you are, how often you leave this inside area... it could be a lot or a little. Either way, you want to be protected. I don’t make the rules. 

“Windows protect from most UVB rays (the ones that burn you) but not many UVA rays (the ones that cause premature skin ageing).”

But it's winter.

“Yes, I’m in Melbourne and it’s freezing. It was a max of 15 degrees here yesterday and the UV index hit 3. Anything above (and including) 3 and the Cancer Council recommends application. 

“If you’re in NSW/QLD/WA/NT then the UV index probably isn’t dipping below 3 much, if at all, during the year. 

Unless you want to be glued to the Bureau of Meteorology app all day furiously checking the UV index, just save yourself some peace of mind and apply in the morning so you’re covered.

“Side note, the UV index is based primarily on UVB rays, so again, it isn’t always the best indicator of UVA rays which are present all year round.”

So to be crystal clear (geddit?!), does glass give me ANY protection?

“Just protection from most UVB rays, but windows allow between 80-95 percent of UVA rays through. You won’t get sunburnt sitting in front of a window, but you will get all the fun stuff associated with UVA damage including: pigmentation, skin sagging, fine lines, wrinkles.” 

But what if I'm inside all day and not in any direct sunlight, or if it's raining?

“Like all day? Like you do not leave the inside of your house at ALL? Then you’re probably fine although I’d recommend getting some fresh air. UVA rays still penetrate through clouds so even if it’s raining or cloudy and you’re outside or near a window you need to wear SPF.”

Fine. My moisturiser has sunscreen in it, is that enough for inside only days?

“If you’re literally inside only all day, and not near windows, yes. If you leave the house for more than five mins, no.”

Right. Well my foundation has sunscreen in it, is THAT enough for inside only days? 

“As above.”

Okay. So then is the sunscreen in my day cream or foundation ever really enough? 

“As a general rule (assuming you’re not inside in a windowless room from sun up to sun down), SPF in moisturiser or foundation isn’t enough to protect you sufficiently.

“First of all, many of those products aren’t made here so not tested in our conditions, therefore they don’t need to be approved by the Therapeutic Goods Administration (TGA) as they’re not considered a ‘primary SPF’. 

Secondly, you’re likely not applying enough to get the protection listed on the bottle. This is especially the case for foundations.”

Cool, cool. So I’m going to wear sunscreen inside. How much should I apply to my face?

“This is the topic of much debate as it’s not really prescribed by many brands, or the TGA.” 

“Cancer Council says 1 teaspoon for face, neck and chest, but during SPF testing a quarter of a teaspoon for face and ears is applied - and then more for neck and chest. 

“We try to make it easy at Ultra Violette and recommend a certain number of pumps or droppers so people have an understanding of what that looks like. Nobody is literally using a teaspoon to measure out their SPF every day!” 

*Puts teaspoon back in drawer*.

If I've been inside all day but pop out at 5pm to get my kid from daycare, should I reapply my sunscreen?

“If you’ve applied in the morning and you’re not going to be out for long, you’re probably fine. If it’s a particularly hot period, like in the middle of summer or the UV index is super high, I’d probably reapply. Maybe not a full application but just something to make me feel like I’m not completely exposed.”

You really love sunscreen. Anything else you want peeps to know?

“Look, SPF application is the good kind of habit you just want to become automatic. Like brushing your teeth. You’re not going to skip a day of brushing your teeth just cos you don't think you’re going to see anyone, right? 

“I just think wearing it every day means you’re ingraining that habit and means that you’re covered if you do go outside to get a coffee/lunch/the delivery Aus Post didn’t even check to see if you were home for.  

“At the very least, apply once in the morning as a part of your skincare routine regardless of the weather and you really will thank yourself later.”

Okay very good, so we all wear sunscreen every day now, yes? Here’s a bunch of ace ones.

Ultra Violette Queen Screen, $47

Image: Supplied. 

Mecca To Save Face, $40

Image: Supplied. 

La Roche Posay Anthelios XL, $29.95

Image: Supplied. 

Cancer Council Daywear Moisturiser, $13.50

Image: Supplied. 

NIVEA SUN UV Face Shine Control Cream, $11.99

Image: Supplied. 

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