For anyone who lives in Australia, awareness of sun protection is a part of life—like wearing your helmet around magpies or checking for huntsman spiders behind the toilet door.

Most of us grew up being told to slip, slop, and slap: slip on a T-shirt, slop on some sunscreen, and slap on a hat before we went outside.

We all know that we should wear sunscreen. But if we’re honest, many of us frequently forget it, skip it, or save it only for the days when we know we’ll be down at the beach for hours.

To find out if our current sunscreen habits are up to scratch, we researched the most common questions about sunscreen usage— and spoke to an expert for some clarification along the way.

How does sunscreen work?

“Sunscreen is a mixture of products that both absorb and scatter UV radiation so that it minimises the amount that reaches our skin cells,” says Dr. Matt Vickers, a GP who specialises in skin health.

Sunscreen absorbs UV rays by collecting them and converting them to mild heat, or reflects these rays by bouncing them off the body and scattering them [1]. There are two kinds of UV rays that we need to be aware of: UVA and UVB. Both can cause sunburn, and both can contribute to our risk of skin cancer.

Most sunscreens protect against UVB rays, but UVA rays can also penetrate the skin and may actually penetrate deeper than UVB rays. For this reason it’s important to use a sunscreen that protects against both rays: this is called a broad-spectrum sunscreen.

The amount of protection a sunscreen offers against the sun’s rays is measured in SPF: Sun Protection Factor.

In Australia, the Cancer Council recommends that we use nothing lower than SPF 30+ protection, which offers protection against 96.7% of UV rays [2].

An SPF of 50+ can offer protection against 98% of UV rays. While it doesn’t seem like there’s a huge difference between the two, we reckon that the more protection you have against the sun, the better.

A broad-spectrum, SPF 50+ sunscreen is our go-to whenever we’re in the sun. ‍

Is it true that sunscreen is dangerous to use?

There are rumours that sunscreen can cause skin conditions rather than preventing them, but this is not true.

The Therapeutic Goods Administration and the Cancer Council have extensively and rigorously researched the safety of sunscreen, including sunscreens that contain nanoparticles and chemicals, and have found that they do not pose a health risk [3][4].

Do I have to wear sunscreen every day?

We should be wearing sunscreen every day—even if we’re just heading out of the house quickly, even if it doesn’t look that sunny outside, and even if we can’t be bothered!

No matter the weather or the time of year, the sun continues to produce and emit UV rays that can be harmful to our skin.

While the UV index is generally lower during winter than it is during summer, there is no day that has zero UV rays and as such, there’s no day when we should be wearing zero sunscreen.

If you’d like to see for yourself how high the UV index is in your city on any given day, you can use the UV Index tool developed by the Australian Radiation Protection and Nuclear Safety Agency. It’s available here.

Should I wear sunscreen indoors?

With more and more people working from home, some of us are beginning to wonder if we should wear sunscreen indoors.

The jury seems to be out on this—we couldn’t find any research or studies to support the claim, but we’re going to say that it comes down to common sense. If you’re at home—or in the car—and sitting in front of a big window in direct sunlight, we think it wouldn’t hurt to pop some sunscreen on.

But if your nearest window is across the room and there’s no sunlight pouring in, we think you’re okay to go without.

What will happen if I don’t wear sunscreen?

“Sunscreen has a number of benefits including preventing photoageing, reducing rates of skin cancer and preventing burns or changes to skin pigmentation, which is a sign of skin cell distress,” says Dr. Vickers.

“Sunscreen helps prevent damage to skin cells that can lead to changes to our appearance such as wrinkles, freckles and uneven pigment. It has also been proven to prevent skin cancers with reductions in melanoma and non-melanoma skin cancers seen with regular sunscreen application.”

So sunscreen can prevent extrinsic ageing and hyperpigmentation—which most of us are keen to avoid—but that’s not the only reason we use it.

By reducing our exposure to UV radiation, we reduce our risk of cancer.

Over 95 per cent of cancers in Australia are caused by UV radiation, and two in three Aussies will be diagnosed with skin cancer by the time we turn 70.

That’s a shocking statistic, because it means that we’re technically more likely to get skin cancer than not [5]. Australia has one of the highest rates of skin cancer in the world [6].

Even if you’re not interested in protecting the appearance of your skin, we want you to protect the health of it.

We can’t be more serious: you really have to wear sunscreen.

I haven’t worn sunscreen in the past. What should I do?

The best time to start wearing sunscreen was years ago, but the second-best time is now. If you’ve never worn sunscreen before, we insist that you go out and pick up a bottle.

There are all sorts of sunscreens out there, and many of them are non-comedogenic (made to reduce the chance of clogged pores) and designed to look invisible once they’re on your skin.

Yes — the thick, white, gross sunscreen of your childhood is long gone!

We also recommend booking in with your doctor to get a skin check. Even if you’re a regular sunscreen user, skin checks are important.

In a skin check, your doctor will look all over your body to check that your moles and freckles look normal—and they can show you how to check your own moles and freckles at home as well.

Particularly in Australia, the sun’s rays are harsh and difficult to avoid. We only get one chance to properly protect our skin against the sun—let’s make sure we do it the right way.

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