More and more the actual culprit in skin cancer is appearing to be the overconsumption of omega 6 oils. They are highly rancid in the body, and become moreso when exposed to certain UV rays, apparently(particularly in the presence of low antioxidants). People of varying shades have lived in high sun regions for eons without developing skin cancer, and increases in skin cancers are found almost exclusively in in people who have turned to a western dietary lifestyle.