Sun, sunscreen, vitamin D and cancer

21 Jan 2009 12:39 PM - A confusing situation

 It's hot out there and it's just so easy to get sunburnt.  Like many people (especially of my generation), I spent the summers of my youth covered in baby oil and basting for hours in the sun (after all it wasn't really summer unless you had lost at least a couple of layers of skin).  However, having had numerous skin cancers removed over the last 10 years my desire for a tan has diminished considerably.

The question is, do you try to avoid the sun entirely or do you cover yourself in sunscreen in the belief that it is the safe option.  Unfortunately, it appears there is no simple answer. 

The protection in sunscreens usually comes from chemicals such as zinc oxide.  Generally speaking the particles in these chemicals are large and hence not easily absorbed by the skin (think the zinc cream white nose).  However, through the wonders of science, manufacturers can now reduce these constituents to the size of nanoparticles which are much, much smaller and more readily applied.  Consequently, there is some question surrounding the safety of sunscreens containing nanoparticles as their long term use has not been well studied and it may be that they are absorbed through the skin and into our cells with possible health implications. 

Furthermore, exposing your skin (without protection) to sunshine is the easiest and cheapest way to get the essential nutrient, vitamin D.  In spite of our hot, sunny climate, a surprising number of Australians are found to have low levels of vitamin D.  This vitamin is vital for our health and low levels have been implicated in many diseases including osteoporosis, some cancers, multiple sclerosis and psoriasis.  Dietary sources of vitamin D include eggs, cold-water fish and cod liver oil.  Taking a good quality supplement is another alternative to maintaining your vitamin D status. 

So, my suggestion is try to get some sun exposure early in the day, cover up in the heat of the day, don't use sunscreens as an excuse to spend hours in the sun and if you are worried about your vitamin D levels, they can be easily measured by a simple blood test.  Of course, if you are at increased risk of developing skin cancers then you need to be extra cautious and perhaps looking for other sources of Vitamin D would be advisable.

In good health,

Kaye Wright