May
2008
UVA the trigger?
Melanoma; it’s a puzzle with peices missing. I’ve thought about this one long and hard, what if UVB doesn’t matter? Let me entertain yet another example of where we might be going drastically wrong.
“Most sunscreens do a good job blocking UVB, but fewer sunscreens filter out most of the UVA, so they do not help to prevent the beginnings of melanoma formation … The precise wavelengths of ultraviolet that contribute to the formation of skin cancer still need to be sorted out.” Source
We could be getting damaged melanocytes without the sunburn, right so how can you get skin cancer without being sunburnt? Well this question has never been asked. Nor has the “stay out of the sun between 11am and 4pm” bit of sunsmart been challenged.
UV index varies
I’ve noticed that peak UV hours and the times where I burn are after 4pm and before 6pm, not only the hottest part of the day but also what’s to say the UV index isn’t lower at 12pm because of cloud cover and greater at 6pm because of clear skies?
UVB might not be doing the damage
There are three types of UV radiation, and each type bassically vibrates the skin more or less. UVB is often connected to the burning effect the sun has on skin general rule is UVB = burning. Even if you get factor 50 sunscreen, SPF only measures effectiveness against UVB radiation not both UVA and B. UVA is often thought to really only age the skin and thus sunscreens have been utterly useless against UVA, but isn’t cancer linked to the ageing process?
Still we think UVB triggers most melanoma’s, but how can this be if most people with melanoma admit to making good use of sunscreens? UVA protection is measured by the star rating not the SPF and the star rating is really only a recent introduction and Ambre Solair’s UVA photostable filters have only just made it from Europe to the USA.
Sunscreens never protected against melanoma?
What if in the 1980’s and 1990’s we were told sunscreens would protect us, but it turns out that in fact it’s UVA which triggers melanoma and thus the protection we thought we had, simply never existed and still may not exist? Some retailers don’t sell lower than SPF 15, but what if it’s SPF 30 and still UVA rating of 1? Isn’t that also as bad as stocking SPF 2?
What if you can get melanoma skin cancer without a long history of sunburn, ok it is a bit far fetched, a lot of people did burn most of the time by accident and without intending to. But what if you can damage your skin even if you don’t burn, if you are genetically unable to produce melanin? What if it turns out UVB is attributed to non-melanoma and UVA to melanoma, suddenly you would need to advise people at risk of melanoma to not rely on SPF as a guide but the star rating.
Let’s get sunSmarter?
Everything you know is wrong, everything I know is slightly less wrong and everything they know is really wrong, so let’s re-write this. sunSmart needs to get smart about the UV index, for instance it might be safer to go out at 12pm under cloudy skies than it is to go out at 5pm under clear skies. so the 11am - 4pm curfew needs chucking out in favor of words on suncreen bottles explaining the UV index, what it is and how to check it for your location.
sunSmart also need get smarter about the advice given out to people at risk of melanoma and non-melanoma, each risk group needs different messages not the same messages and I was pleased to see that at least that bit of my campaign got through to Cancer Research UK.
Re-write the rules!
