Australia is one of the sunniest countries on earth, with the east coast clocking at least 6+ hours of brilliant sunshine on average, each day. But despite our excess of wide blue open spaces, Australians are lagging when it comes to Vitamin D. “There isn’t much vitamin D in food – at least 80 per cent comes from sunlight exposure – and in Australia, we have surprisingly high levels of vitamin D deficiency considering our climate, particularly in winter,” explains the University of Sydney’s Professor Rebecca Mason, an expert on bone health.
Why Vitamin D matters for bones
Inevitably, maintaining healthy bones becomes more difficult as we age – especially for women. That’s when Vitamin D becomes especially important. “Every day your body loses calcium, predominantly in urine. That calcium loss is worse in women after the menopause,” explains Professor Mason. “You have to replace that calcium and to do that, you need to not only eat calcium but be able to absorb the calcium that you’re eating. And vitamin D – which we for the most part, produce from sun exposure – helps with the absorption.”
To sun, or not to sun?
The catch is that the same UV light that helps us make Vitamin D, is also the same UV that causes skin cancers. So how do get our sunshine fix for healthy bones whilst staying sun safe? “It’s a trade off all the time,” says Professor Mason.
Last year, Professor Mason contributed to new guidelines in collaboration with peak bodies across both the bone medicine and cancer prevention sectors – including Healthy Bones Australia, the Cancer Council, Royal Australian College of Dermatologists and the Australian and New Zealand Bone and Mineral Society. The result is a new “official word” on sunlight exposure, Balancing the harms and benefits of sun exposure, which offers new guidance based on different complexions. “The new guidelines have been categorised based on three different skin types,” says Professor Mason.
In summary, here’s what the new guidelines have to say about getting your fix, without putting yourself at unnecessary of skin cancer:
- For people with darker skin (deeply brown to black skin), it takes longer sun exposure to maintain vitamin D levels. Fortunately, people with dark skin are considerably less prone to getting skin cancer on sun exposed sites, so while they should wear sunglasses, they only need other sun protection measures if they are out in the sun for a long time (>2 hours)
- For people with darker white, olive or light brown skin, adequate vitamin D status can be obtained by short and regular exposures to sunlight, best from mid-morning to mid-afternoon. After this short exposure, then sunscreen and other sun protective measures are recommended if UV is 3 or above.
- For anyone with pale skin or a personal history or family history of melanoma (or other skin cancer) or lots of moles or uncommon moles on skin or taking immunosuppressant medication then sun protection is recommended at all times when UV index is 3 or above. These people may need to speak to their doctor about vitamin D supplements.
The truth about sunscreen
So what does that mean for sunscreen? “This is a tricky area because sunscreen is designed to block the UVB that causes DNA damage, redness, sunburn and skin cancers. But it’s that same light that makes vitamin D,” says Professor Mason.
Research into sunscreen use and efficacy shows when sunscreen is put on in a laboratory setting as directed, people simply don’t make vitamin D.
But there’s a catch: “Here’s the paradox; Even when they are trying to use sunscreen properly, people tend not to put sunscreen on everywhere, not at the recommended concentrations and they don’t reapply it. And even with all that, it still does reduce skin cancer,” says Professor Mason. “If you’re out in the sun, and wearing sunscreen, in reality you’re probably still going to make some vitamin D because you might not have applied it everywhere. So, sunscreen helps protect your skin, but the way people use it – the fact they don’t use it as directed – means you will still make vitamin D.”
Going out in the sun most days, with some skin exposed (eg short sleeves), at least for a few minutes, for most people who don’t have a history of sun sensitivity or other health conditions that make them especially vulnerable to UV, is a good idea so long as you follow the guidelines for sun protection based on your complexion. “Sunglasses are recommended for everyone no matter what your skin type to protect eyes from sun exposure,” adds Professor Mason. “The other thing to understand, while we’re all very aware of the risks, sunlight exposure has some benefits. One of the benefits is making vitamin D. Sunlight also dampens your autoimmune system so that people who live further away from the equator, for example, are more prone to get autoimmune conditions like multiple sclerosis, type one diabetes and so on.”
So there you have it. The 411 on a very complex topic. It’s a balancing act, but it’s one we can all navigate better with these new guidelines that reflect the changing face of Australian society (literally). If you’re in doubt, or you’re concerned about sun exposure or Vitamin D deficiency – or both – chat to your GP.
