Yep – it’s summer, and you probably think you’ve heard it all before:
“Watch out in the sun.”
“Australia has the highest rate of skin cancer in the world.”
“Be SunSmart, slip slop slap. Blah blah blah…”
Well – here are a few things you might not have thought of.
What kind of skin are you protecting?
Billy Connolly has a line about Scottish people starting blue. They need a few days in the sun just to get to being white! It’s true that people with pale skin are at the highest risk of skin cancer. Their skin type has been adapted over thousands of years to suit the very low Ultraviolet Radiation (UVR) climates closer to the north and south pole. That skin type maximises the little sun they get – but is easily damaged when they are exposed to the extreme levels of UV we experience in an Australian summer.
Non-melanomas kill too
Each year, Australians spend more than a billion dollars treating skin cancer, and more than 2000 of us die as a result of skin cancer – two thirds of those deaths are men and about a quarter are not even due to melanoma. Squamous cell carcinoma (SCC) is a type of non- melanoma skin cancer (NMSC) and is so common we do not even count it through our mandatory cancer registries. Yet it killed 543 Australians in 2011 and of those almost 355 were men. What’s most alarming, is that most of these were preventable.
Most sunscreen users get half the sun protection claimed on the label (or less!), as users commonly apply too little sunscreen to achieve the SPF level listing on the container. A good guide to using to right amount is to use one teaspoon per limb: one for each arm and one for each leg, one for the face and one for the front torso and one for the back. And use more if you are bigger, and a little less for kids. It’s important to use sunscreen in addition to protective clothing (like rashies and boardies for swimming), and a good hat! Think of sunscreen as a good back up plan, but not an ideal first line of defence against the sun. Sunscreen can wash off, or rub off when we towel down or when we brush against our clothes or the sand.
Shade ain’t shade.
Sitting or lying in the shade for hours expecting full protection can be a worry. Many commercial shade cloths were designed for horticultural purposes and can offer very low sun protection levels – equivalent to an SPF of 5 -10. Lots of Australian native trees (like the classic Eucalypt or Gum Tree) feature small leaves and a sparse coverage. A simple test might be – can you see your own shadow clearly when you are in the shade? If so, lots of UVR is getting through so use sun protection plan B (clothes, hat, sunscreen etc). And ambient or scattered UV in the wide open skies, like out on a beach, accounts for 50% of the UV that reaches our skin. So even a good beach umbrella only offers a SPF equivalent of about 2 – 3. If you can see lots of sky – there will be lots of ambient UV.
But what about Vitamin D?
More than three quarters of Australian adults have healthy levels of Vitamin D. And about 6% have levels that are considered too low (below 30nmol/L), while a similar proportion of us have levels that may be too high (above 100nmol/L). A few minutes in the mid-morning or mid-afternoon sun a few days a week is enough for most people to maintain good levels of Vitamin D. A sunburn means way too much sun and without a doubt, an increased risk of skin cancer.
For more information on skin cancer go to cancer.org.au More detail plus guidance on the latest skin cancer treatment options are covered in the new book Sun, Skin and Health, edited by Terry Slevin for CSIRO Publishing.