Australians are all too familiar with the sun safety ads that began in the noughties and included the iconic line of: "tanning is skin cells in trauma". While we know the risks that tanning comes with, you might be wondering if your skin is still exposed to tanning while you're wearing sunscreen.

With this in mind, we've collated all of the information you need to know about tanning, sunscreen and how to use it to adequately protect your skin.

How does sunscreen work?

While you've probably been using sunscreen every day for years, you may not know exactly how it works to protect the skin.

Well, it works by absorbing, reflecting, or scattering the sun's harmful UV rays and this depends on the type of sunscreen you use. Sunscreen products will contain either chemical or physical blockers that can help protect your skin from sun exposure.

The effectiveness of sunscreen depends on several factors, including the type of sunscreen, the amount used, and how often you reapply sunscreen [1].

Chemical sunscreen vs physical sunscreen

There are 2 types of sunscreen: chemical and physical sunscreen.

Chemical sunscreens contain organic (carbon-based) ingredients such as avobenzone, octinoxate, and oxybenzone. These compounds absorb UV rays and convert them into heat, which is then released from the skin.

The consistency of chemical sunscreens usually makes them easier to blend in and apply.

Physical sunscreen

Physical blockers or mineral sunscreens include ingredients like zinc oxide and titanium dioxide. These sit on top of the skin and reflect or scatter the UV rays creating a physical barrier from the sun.

Physical sunscreen is more suitable for sensitive skin, however, it can be more difficult to apply. Both chemical and physical sunscreens are effective at protecting the skin from the sun's harmful UV rays.

The best type of sunscreen for you depends on your skin type and personal preferences. It's important to choose a sunscreen with broad-spectrum protection (protecting against both UVA and UVB rays) and to apply it generously and regularly to protect your skin from sun damage [2].

The difference between UVA and UVB rays

Ultraviolet or UV rays are the nasty beams of heat that are produced by the sun. These are divided into 3 types according to their wavelengths — UVA, UVB, and UVC waves.

UVC waves are absorbed into the earth's atmosphere and don't reach us at all. This is why you might not be as familiar with these as you are with UVA and UVB rays.

So, what is the difference between these more well-known waves? Well, UVA rays are longer and penetrate deep into the skin. These are the ones that cause wrinkles and other signs of skin ageing.

UVB rays, on the other hand, are shorter, affecting the surface of the skin and causing sunburn. While UVB rays might not be as long as UVA rays, each is dangerous and can cause UV damage and skin cancer.

A broad-spectrum sunscreen will protect against both UVA and UVB rays [3].

Can you still tan with sunscreen on?

The good news is, no, you can't tan with sunscreen on. As the name suggests, sunscreen works to screen, not block, the sun when it reaches your skin.

But, according to Cancer Council, if your "sunscreen is properly applied to do its job of reducing UV radiation exposure, it prevents the biological process of tanning" [6].

So, if used correctly, sunscreen will help to protect your skin from tanning. Be sure to use it in conjunction with other protective measures like wearing a hat, sunglasses and clothing that covers your body.

How to choose the right sunscreen?

Not all sunscreens are created equally so choosing the right one can be tricky.

Here are some tips for choosing the right SPF.

• Opt for broad-spectrum sunscreen to protect you from all forms of UV
• Ensure your sunscreen has a sun protection factor of at least 30 or higher
• Get water-resistant sunscreen, even if you don't plan on swimming [4]

Software's Daily Sun Defence SPF50+ filters out 98% of UV rays thanks to its UVA and UVB filters. The non-greasy and non-comedogenic formula effectively protects you from the sun and may help reduce the risk of photoageing, sun spots and some skin cancers.

How does tanning work?

Tanning is the process of making your skin darker through exposure to UV radiation. When you spend time in the sun, UV rays penetrate your skin and stimulate the production of melanin.

Melanin is a pigment that gives your skin its colour, and when it's produced in response to UV rays, it darkens your skin.

There are different types of melanin, which produce different colours. The two main pigment producers are:

• Eumelanin: This makes your skin brown
• Pheomelanin: makes it red or yellow

The amount and type of melanin your skin produces depend on your genetics [5].

Is it possible to tan safely?

No, there is no way to safely tan your skin. Tanning increases your risk of developing skin cancers including melanoma, basal cell carcinoma and squamous cell carcinoma [7].

How to safely spend time in the sun

The best way to stay sun safe is to stay out of the sun as much as possible. But, when you are going out and about during the day, here's how to protect yourself.

Wear sunscreen

Apply an SPF50+ sunscreen 15-30 minutes before going outside and remember to reapply every 2 hours or after swimming or sweating.

Make sure to use enough sunscreen to cover all exposed skin. A broad-spectrum sunscreen is your best friend when it comes to getting complete protection from both UVA and UVB rays. Sunscreen should be an integral part of your morning skincare routine (applied after your moisturiser).

Be sure to always check the expiry date of your sunscreen before using it.

Seek shade

Stay in the shade during peak sunlight hours (10am-4pm) when the sun's rays are strongest. Use umbrellas, trees, or other shade structures to protect yourself from the sun.

Wear protective clothing

Wear long-sleeved shirts, pants, and a wide-brimmed hat for skin protection from the sun. Choose clothing made from tightly woven fabrics that provide sun protection.

Wear sunglasses

Wear sunglasses with UV protection to shield your eyes from the sun's harmful rays.

Stay hydrated

Drink plenty of water to prevent dehydration, especially when spending time in the sun.

Check the UV index

Check the UV index before going outside. The higher the UV index, the greater the risk of sunburn and skin damage. Take extra precautions when the UV index is high.