Four questions to help pick the right sunscreen this summer

Do you know what those SPF numbers really mean? Or which sunscreens to avoid if you have sensitive skin? Make sure you’re buying the right product for you with some quick facts from the experts

PUBLISHED : Sunday, 23 July, 2017, 9:32am
UPDATED : Monday, 24 July, 2017, 6:07pm

Choosing a sunscreen can be confusing. Shelves are filled with multiple brands advertising varying SPF levels, all claiming to care for and protect your body’s largest organ – your skin.

So what should you be looking for when buying your sun protection? We turn to the experts with some important questions to help your decision this summer:

What does SPF mean?

SPF stands for sun protection factor. SPF is not a specific ingredient; it relates to the amount of time it takes for redness to appear on skin exposed to ultraviolet (UV) radiation after applying the product compared with when no product is used at all.

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“For example, if it takes 10 minutes for unprotected skin to show redness, then [skin with] an SPF30 sunscreen correctly applied, in theory, will take 30 times longer, or 300 minutes to burn,” says Heather Walker, chair of Cancer Council Australia’s skin cancer committee.

Is SPF130 really any better than SPF30?

According to Hong Kong dermatologist Joyce Tang, SPF levels are not regulated by a government body in Hong Kong like they are in countries such as Australia. In Hong Kong, sunscreens have been seen to go as high as SPF130, but in Australia sunscreens cannot be advertised any higher than SPF50.

Walker says that in Australia, experts have recommended that SPF labels should be capped at 50+ as lab results can be very different depending on circumstances. “Consumers can be lulled into a false sense of security, thus neglecting other important sun protection measures and not using the sunscreen effectively,” she adds.

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However high the numbers go, the Hong Kong Cancer Fund and Walker both recommend that people should wear SPF30 sunscreen or higher when going outside. Walker says that once you get beyond SPF30, the difference in protection is actually quite small. “SPF50+ filters out 98 per cent of UVB radiation compared to 96.7 per cent of UVB blocked by SPF30+,” she says.

What are physical and chemical sunscreens?

Tang says consumers also need to look at the sunscreen’s ingredients. “There’s physical sunscreen and chemical sunscreen. They both work very well but some people are probably more allergic to chemicals, so they have to switch to physical sunscreen.”

Physical sunscreens, such as zinc, are often thicker, opaque and harder to apply, while chemical sunscreens are usually more fluid and odourless.

Chemical sunscreens can sometimes include the ingredient avobenzone. New research suggests that when avobenzone is exposed to a combination of light and chlorinated water, “it can degrade into some very harmful compounds, some of which are known carcinogens”, says Daniel Aires, a dermatologist with the University of Kansas Medical Center. “What isn’t known is how much is absorbed into the skin, or if it’s to a level that can cause or potentially increase the risk of cancer.”

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Can you ever be completely protected from the sun?

No sunscreen offers 100 per cent protection from UV radiation. “It’s not a suit of armour against the sun,” Walker says. To achieve the SPF level on the label, she says sunscreen must be applied liberally (seven teaspoons or 35mls of sunscreen) at least 20 minutes before heading out into the sun and reapplied every two hours after swimming, sweating or towel drying.

The sunscreen you buy should also be broad spectrum and water resistant. Broad spectrum sunscreens protect against UVA and UVB, two types of UV radiation produced by the sun. “UVB is the main cause of sunburn, but both UVA and UVB contribute to increased skin cancer risk,” Walker says.

Along with sunscreen, people going outdoors should wear a hat and sunglasses, and wear sun protective clothing, covering as much skin as possible.

Additional reporting from Tribune News Service