The Down-Low On Vitamin D: How Much You Need And How To Get It Safely

We asked, the Cancer Council answered.

When it comes to the sun, us humans are in a bit of a pickle. Each blinding ray is a double-edged sword, so to speak.

On one hand, the sun’s ultraviolet (UV) radiation is the best natural source of vitamin D, which our bodies need for strong bones, muscles and overall health.

You can get some vitamin D from fatty fish such as salmon, and supplements, but straight from the sun is better.

But UV radiation -- which includes UVA and UVB rays -- is also the main cause of skin cancer, the three main types being basal cell carcinoma, squamous cell carcinoma and the most serious, melanoma.

It's all a bit scary, and enough to make you want to run inside, close the curtains and never come out. But a life without adequate sun or vitamin D can in some cases lead to softened bones -- called osteomalacia in adults and rickets in children -- and weakened muscles.

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So how do we stay healthy, while staying sun-safe?

Heather Walker, chair of the National Skin Cancer Committee at Cancer Council Australia, is one of the most-equipped people to answer that question.

"Vitamin D levels change naturally with the seasons," Walker told 10 daily.

In summer, most people make enough vitamin D because we spend more time outdoors when UV levels are high -- that is, they're above 3 on the UV Index.

A few minutes of sun exposure mid-morning or mid-afternoon is all most people need to hit their target in summer -- typically between mid-August to the end of April in southern states.

"Don't forget that a combination of sun protection measures is recommended, even for people who have been diagnosed with a vitamin D deficiency," Walker said.

In late autumn and winter in some southern parts of Australia, the UV Index can fall below three, meaning you might need to change up your vitamin D routine.

Instead of stepping outside mid-morning or mid-afternoon as in summer, it's an idea to spend time outdoors in the middle of the day with some skin uncovered in the cooler months.

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During that period -- typically from May to mid-August in southern states -- sun protection is not recommended, unless you work outdoors, are near reflective surfaces (like snow), or outside for extended periods.

Outsmarting the sun

Knowing the UV Index of a particular day isn't something you can just guesstimate on your own, and you certainly shouldn't just wing it when it comes to sun protection.

Instead, Walker recommends downloading the SunSmart app. It's free and can save you a lot of grief -- and burnt body parts -- in the warmer months.

Getting your daily vitamin D shouldn't be a more-is-more approach either.

"The body can only absorb a limited amount of vitamin D at a time," Walker said.

Spending extra time in the sun won’t increase vitamin D levels, but will increase your risk of skin cancer.

If that's not enough to curb your sunbathing habits then we don't know what will. That and the fact that Aus has one of the highest rates of skin cancer in the world, with two in three people diagnosed by the age of 70 should do it.

It's also not the best idea to self-diagnose vitamin D deficiency, and use that as a reason to soak up more rays.

According to Walker, those who may be at risk include people with naturally very dark skin, people who spend a lot of time indoors and night workers. If you suspect you might be deficient, her advice is to see a doc, who may advise supplementation.

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SPF is your BFF

Bottom line is if you're stepping out for some vitamin D and the UV Index is over three then sun protection is your BFF.

Although neither Walker or Cancer Council are able to comment on any particular sunscreen brand, Walker did tell 10 daily this: "[we] emphasise that Australians should choose an SPF30 (or higher) broad-spectrum, water-resistant sunscreen together with the other four forms of sun protection -- clothing, a hat, sunglasses and shade -- for the best level of protection in the sun."

If you're really after a ~glowy~ tan then you know what to do -- hit the spray tan booth, not the beach.

Feature image: Getty.