LEF has lots of links to studies like this...they are numerous and growing.
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More and more, it seems to be the simplest things that both prevent and cause cancer.
I no longer wear sunscreen. I stopped using it years ago as I didn't really trust the chemicals involved and there's an old statistic that states something like "since the advent of sunscreens, skin cancer rates have risen 300%" or something like that.
In any case, it appears to be less about the chemicals you rub on your skin than denying yourself vitamin D which really is about the simplest wonder drug out there.
I think a lot of ancient cultures worshipped the sun for good reason.