One minute we hear from the Cancer Council that Australia is the skin cancer capital of the world because we spend too much time in the sun. The next minute I read in the Medical Journal of Australia that a third of Australian adults are vitamin D deficient because we don’t spend enough time in the sun. Who’s got it right?
Not too much. Not too little. Just right. So what constitutes ‘just right’ in terms of sun exposure?
Ten minutes a day, preferably in the middle of the day, immediately after you’ve applied your sunscreen. Why? Because it takes sunscreen 10 to 20 minutes to take effect. That means the sun’s UVB rays will reach your skin and convert cholesterol to vitamin D during the time that it takes your sunscreen to work. Exposure to the sun through windows is inadequate because glass tends to block UVB light. If you can’t get outside every day, aim for a total of 60 minutes a week, divided up as best you can. Twenty minutes three times a week is also fine. However, just as it isn’t a good idea to save your weekly alcohol quota for a weekend binge, don’t save up your sun exposure for one hour every Sunday. Spread it out through the week as much as you can to minimise the risk of sunburn and skin cancer.
Certain classes of antibiotics, antidepressants, anti-inflammatories and blood pressure medications can increase your sensitivity to UV radiation so check with your doctor if this is the case and reduce your sun exposure as required.
People still ask me if there is a direct link between sunburn and melanoma (the deadliest form of skin cancer)? Yes.
Repeated sunburn is the cause of 95% of melanomas. On an average summer weekend in Australia, 14% of adults, 24% of teenagers and 8% of children get sunburnt – in the pool, on the beach, in the park, having a BBQ, doing the gardening or participating in water sports.
What about cooler, overcast days? UV radiation can still be strong so the message remains:
- Slip on protective clothing
- Slop on broad spectrum, water-resistant SPF30+ sunscreen and reapply every two hours
- Slap on a hat
- Slide on some sunglasses (excessive sun exposure can lead to cataracts)
- Seek shade
As of January 2016, commercial solariums were banned throughout Australia. Was this necessary? Yes. I applaud the government’s initiative because solariums emit UVA and UVB radiation, both of which cause cancer.
One other question I’ve been asked is whether fake tans provide protection from sunburn and skin cancer. The answer is no, despite the claim of some products. You need to take the same precautions even if you have an artificial tan. The more naturally dark your skin, the more melanin you produce and the less likely you are to get burnt. However even dark skinned people need to follow the same Slip Slop Slap and Slide advice.
So why are we hearing that vitamin D is the new panacea? Can vitamin D reduce the risk of multiple sclerosis and Alzheimer’s disease? And can we get enough vitamin D from food, thus eliminating the need to spend time in the sun?
I’ll address these questions in my next HEB.