Australian sunscreen has been in the news a lot in the past year and it may have left you wondering how you can best protect your skin — and with kids heading back to school, their skin too.
Testing commissioned by consumer group Choice revealed some popular sunscreens failed to meet their sun protection factor (SPF) claims in June, and a number of sunscreens have since been recalled.
But even if your sunscreen isn't under scrutiny, it could be that your application is letting you down.
Many of us simply don't apply enough, according to Anne Cust, cancer epidemiologist and the director of the Daffodil Centre.
This is what three experts had to say about how to get the best protection from your sunscreen this summer.
How do you apply sunscreen correctly?
Professor Cust says Australia has the highest rates of skin cancer in the world, "mainly due to our very high ultraviolet radiation levels from the sun".
Sunscreen is one of our "five key sun protection measures", along with protective clothing, a broad-brimmed hat, seeking shade and wearing sunglasses.
A dermatologist at Sydney's Liverpool Hospital, Deshan Sebaratnam, says you should apply an "adequate amount" if you follow the teaspoon rule.
Use about 1 teaspoon or 5 millilitres for each arm, each leg, the front of your body, the back of your body and again on your face, he says.
Or as Professor Cust says "about 1 teaspoon per body part".
Dermatologist Cara McDonald recommends double-coating sunscreen on high-risk areas, such as your face and the tops of shoulders.
She compares it to painting a wall, when there's "patchy bits" after the first coat but it's consistent after a second.
Dr McDonald says sunscreen is also ideally applied twenty minutes before going out in the sun, giving it time to absorb into the skin and create a protective barrier.
This is important when it comes to chemical sunscreens, but it may help you get better coverage with mineral options too, she says.
If kept in your car it might not be at its best
Dr McDonald suggests checking the expiry date of any sunscreen lying around at home and considering where you store it.
"If it's stored in a really hot environment — like left in the car — those things can break down the sunscreen properties as well."
Professor Cust says if it has been stored in your car for a long time, "you might be better off buying a new one just to make sure you're getting a really effective sunscreen".
Dr McDonald also advises against mixing your sunscreen in with other products. It "can change the efficacy of your sunscreen".
Do I need to reapply sunscreen if I sweat?
The advice from experts is to reapply sunscreen every 2 hours regardless of conditions but there are times you may want to do it more regularly.
Dr Sebaratnam says "some of the sunscreen is lost" any time you sweat or get your skin wet.
When you're sweating your skin might also experience friction which can impact the longevity of your sunscreen, Dr McDonald says.
For example, "if you're sweating and then wiping your face with a towel … you're going to rub it off a lot more than if you're just sweating".
Dr McDonald says if you've wiped your face after a big run "you would want to reapply as soon as you have wiped your skin".
How often should you apply sunscreen if swimming?
Professor Cust says sunscreen may wear off more quickly if you're swimming.
She recommends reapplying after removing excess water, such as after towel drying.
"It is easier to apply when the skin is dry as it absorbs better into the skin."
Sunscreen alone isn't going to be enough to give yourself the best protection, Professor Cust adds.
Dr McDonald says wearing a rash vest or sitting under an umbrella or a cabana "reduces the risk" further.
What is the difference between sport sunscreen and regular sunscreen?
Professor Cust says sunscreens rely on the same base ingredients and while there are differences in formulation the biggest differences can come down to how they are marketed.
"My advice is to just try different formulations [and] see what works for you, because there's very different costs and textures and people have different preferences."
While 'sport' specific sunscreen "might be a bit thicker", Professor Cust says "you don't have to buy a sport sunscreen if you're doing a sport".
Dr Sebaratnam says, "ideally you should be reapplying sunscreen every 2 hours regardless of what is advertised on the bottle".
This is general information only. For detailed personal advice, you should see a qualified medical practitioner who knows your medical history.
