The cancer-preventing mineral is selenium — according to Grok. Drink your SelSun Blue shampoo daily,
Brazil nuts have a lot of selenium.
RE: Selenium
When I moved to N.Z., ~1999, I went to the pharmacy for some vitamins. The pharmacists very strenuously and gravely pointed out that any multivitamin I chose MUST have selenium in it as modern farming had depleted it from the soil.