Growing evidence about the health importance of sun exposure and genetic differences in the population have prompted Australia to adopt new sun safety guidelines.
The research informing the update was published in the Australian and New Zealand Journal of Public Health on Tuesday, and led by Prof Rachel Neale from the QIMR Berghofer medical research institute in Brisbane.
The guidelines are endorsed by health bodies including Cancer Council Australia and the Australasian College of Dermatologists.
“A major step forward for this position statement is that it does recognise that we have a diverse population and that sun protection is less critical for people with very dark skin,” Neale said.
People with dark skin are at the highest risk of vitamin D deficiency. They do not need routine sun protection unless they are in the sun for extended periods, the guidelines state.
“But we’re not wanting to undo the sun protection message,” Neale said. “We’re really trying to get the balance right so we can reduce the risk of skin cancer but also enable people to get the benefits of sun exposure.”
Vitamin D is vital for calcium absorption and immune and nervous system function. The body makes vitamin D after the skin is exposed to ultraviolet (UV) B rays from the sun, with darker skinned people usually requiring greater levels of exposure to generate the same amount of vitamin D as those with lighter skin.
“But these updated guidelines are not just about vitamin D production, otherwise we could just tell everyone not to go into the sun and to take a vitamin D supplement,” Neale said.
“There is evidence that UV has got health benefits beyond just vitamin D and so people with deeply pigmented, dark skin who are not at a high risk of skin cancer can get a small amount of sun exposure and get some of the vitamin D and other benefits as well.”
It remains critical for everyone else in Australia to wear sunscreen daily whenever the UV index is forecast to rise to three or above. For much of Australia that applies most of the year.
This provides a “base” level of protection but people should also ensure they reapply sunscreen and use hats, clothing, sunglasses and shade when outdoors to reduce their risk of skin cancer, Neale said.
Pale skinned people remain at the very highest risk of skin cancer and are advised to protect themselves from the sun at all times, and discuss their vitamin D requirements with their doctor.
This high-risk group also includes people with certain risk factors, such as a family history of melanoma, those with a personal history of skin cancer, people who are immunosuppressed, or those who have lots of moles or moles that are large or atypical. These factors may put someone at high risk regardless of their skin pigmentation.
The guidelines identify those with darker white, olive, or light brown skin as having an intermediate risk of skin cancer.
Protection remains very important for this intermediate group but they can spend some time outdoors to maintain their vitamin D levels and gain other benefits of sun exposure.
The amount of time needed outside will vary depending on where people live, the time of day, the time of year and how much skin is not covered by clothing while outdoors, the guidelines state.
The chair of the Cancer Council’s national skin cancer committee, Prof. Anne Cust, said the guidelines aimed to provide people with more specific advice.
“Anecdotally, a lot of people were saying things like, ‘I have to go outside and get my vitamin D’ and we wanted to give extra guidance about how to safely do so,” she said.
