From UV to SPF – our UQ Experts cut through the confusion to answer some burning questions about sunscreen.
CHOICE has recently published results from independent testing on a variety of sunscreens available on the Australian market, focusing on their Sun Protection Factor (SPF).
The results found 16 of 20 sunscreens didn’t meet their SPF 50 or 50+ claims. In response, many sunscreen manufacturers have sent their products for additional independent testing to clarify the results and reassure consumers.
Professor Monika Janda from UQ’s Centre for Health Services Research and Professor Peter Soyer from UQ’s Frazer Institute explain SPF, why it is important and discuss the results of the testing.
What is SPF and why is it important?
SPF is a measure of how well a sunscreen protects the skin from UV rays, the kind responsible for sunburn and a major contributor to skin cancer.
The higher the SPF, the more UV radiation is blocked.
For example:
- SPF 15 blocks about 93 per cent of UV rays
- SPF 30 blocks 97 per cent and;
- SPF 50 blocks 98 per cent.
Professor Janda said SPF is important to reduce the risk of skin cancer, premature ageing and preventing sunburn.
“In Australia, we are advised to wear sunscreen on days when the ultraviolet (UV) index reaches three or higher,” Professor Janda said.
“That’s year-round for much of Australia.
“People can easily check the weather forecast or the Cancer Council’s free SunSmart app to see the UV levels, and ensure they plan ahead to protect themselves from the sun.”
Explaining the testing
Since the release of the data, there has been question over the testing methods used by CHOICE, resulting in many brands conducting their own testing, given the products have previously passed multiple rounds of testing.
Professor Soyer explains that despite the conversation of accuracy around the testing, it’s important to note that all sunscreens tested provided a level of protection of at least SPF 15.
“According to the Cancer Council, the practical difference between SPF 15, 30 and 50, is relatively small when it comes to overall protection,” Professor Soyer said.
“This means that even sunscreens rated lower than expected, may still offer significant defence against harmful UV exposure.”
Does sunscreen actually protect me?
There has been extensive evidence supporting the effectiveness of sunscreen in preventing skin cancer.
A landmark study using SPF 15 sunscreen showed a 40 per cent reduction in squamous cell carcinoma and a 50 per cent reduction in melanoma, two of the most serious forms of skin cancer.
Professor Soyer explains there are many risk factors for developing skin cancer and melanoma.
“UV exposure, fair skin, a history of sunburn especially in early life, a large number of moles or atypical moles and a personal or family history of skin cancer can all increase the risk,” Professor Soyer said.
“The best sunscreen to use, is the one you are comfortable using the most regularly.
“Sunscreen is one tool for protecting your skin, but it should always be used in conjunction with other sun safety.
“This includes wearing protective clothing, seeking shade during peak UV hours, and wearing a wide-brimmed hat and sunglasses.
“Combining these measures offers the best defence against the harmful effects of UV radiation.”
