The ESK blog

USA National Sunscreen Day

26 May 2023

Dr Anne Thomson

May 27th is National Sunscreen Day so we thought now was the perfect time to answer all your questions about sunscreen and why it’s important to use it daily, all year round.

We’ll also look at why we chose zinc oxide as the hero ingredient in our Zinc Shade daily moisturiser suitable for all skin types, yes, even for sensitive skin, dry skin, rosacea and acne-prone skin!

Why is sunscreen so important?

To answer this question, we need a quick primer course on the sun’s rays and what they do to our skin.

The sun’s rays, also known as UV radiation (UVR), come in many forms, the most medically important of which are UVA and UVB rays.

UVB rays are the ones that cause our skin to burn and are linked to about 90% of skin cancers.

Australia is the skin cancer capital of the world, a dubious honour if ever there was one, with the USA a not too distant 3rd place for some skin cancer types. UVB rays are at their most potent in the summer months and in the middle of the day.

UVA rays on the other hand, are present all year round and all day.

They’re responsible for causing almost all of the signs of skin aging and pigmentation. UVA can penetrate glass (unlike UVB) and even penetrates deeper into our skin layers thanks to its longer wavelength.

Once there, it generates damaging free radicals and triggers harmful enzymes that break down our skin’s elastin and collagen, causing the familiar signs of ageing such as fine lines and wrinkles.

UV radiation is also a common trigger for flare-ups of many skin types, including sensitive skin, rosacea and even acne.

Given that our faces are exposed to UVR most days (not just on beach holidays!) it makes sense that we should be incorporating a daily sunscreen into our skincare routines.

OK, OK, I’m convinced! But which sunscreen is best? And what does SPF mean?

We’re so glad you asked because this is one of our favourite topics!

After reviewing all the evidence and testing a TON of formulations, we think we’ve cracked it with our Zinc Shade daily moisturiser.

First off let’s look at SPF. SPF stands for Sun Protection Factor and is a measure of how much UV radiation it takes to cause skin to burn.

The number refers to a multiple of the time required to burn compared to using no product at all.

Let’s say it takes your skin 10 minutes to burn without any sunscreen on under certain conditions and you properly apply enough sunscreen with an SPF 15.

It should now take your skin 15 times longer to burn, or 150 minutes. An SPF of 30 and it should take 30 times longer to burn and so on.

BUT… there are so many factors that affect a sunscreen’s actual level of protection to the user, on the ground, IRL (ie most of us!); the time of year, the time of day, your location, your skin type, how much sunscreen you have applied, how often and so on.

Therefore it doesn’t really tell you how long you can “safely” stay in the sun.

Secondly, the lab tests are pretty much geared to testing the protection from UVB, not UVA.

This means that when you’re trying to work out which is the best sunscreen, you need to look for “broad spectrum” protection: protection from both UVB (burning) and UVA (aging) damage. The SPF alone won’t tell you this.

Why we think zinc oxide is the best sunscreen ingredient for your face

The real reason we love Zinc Oxide is that all the evidence and guidelines support it above other sunscreen ingredients.

Firstly we love zinc sunscreen because it is broad-spectrum, with excellent protection against both UVB and UVA rays. Big tick!

Secondly we love zinc sunscreen because it is a physical sunscreen, meaning it sits on the skin forming a physical barrier that blocks UV radiation by scattering, reflecting and absorbing the harmful rays.

Chemical sunscreens like PABA, cinnamates and benzophenes need to be absorbed into the skin to work; this can make them irritating AND some are even broken down after a short period when exposed to UVR, rendering them no longer effective.

Because it’s a physical sunscreen and sits on the skin, zinc is one of the safest ingredients to use and the least likely to cause irritation.

This makes it an ideal sunscreen for people with sensitive skin, rosacea and even acne-prone skin.

In fact, based on the data currently available, the FDA (in the US) has declared Zinc Oxide to be one of only two ingredients that are generally accepted as safe (GRASE).

And finally, we love the formulation of zinc oxide in our Zinc Shade.

Many physical sunscreens can feel slimy or heavy on the face and give a ghostly white sheen.

Our Zinc Shade, after much trial and error, has a lovely matte but hydrating finish that can be worn every day and under make-up.

Of course, sunscreen is just one aspect of protecting your face from UVR; don’t forget your hat, sunnies and seeking shade in the middle of the day.

When it comes to your daily face sunscreen, our Zinc Shade ticks all the boxes by not only protecting skin from the most damaging and aging UV rays but also moisturising and not irritating even rosacea, dry, sensitive or acne-prone skin. Win-win!

Zinc Shade

Zinc Shade is a lightweight matte day cream and primer. Its non-greasy, matte finish allows for smooth application and works well under makeup.

We spent countless iterations perfecting this lightweight, non-greasy formula to avoid the typical white cast and thick feel of zinc products. The results? A matte finish that works beautifully under makeup. With well tolerated matte finish, it's also well suited to irritable and blemish and bump prone skin. With SPF 15 it also provides broad-spectrum sun protection against UVA and UVB rays.

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