"... parasites are the number 1 human disaster. From my research since then, I've come across quite a few articles that support this, but they are all on product websites...Do 85% of us really have worms inside us that are harming us?"
The New York Times, deferring to estimates from the U.S. Centers for Disease Control "CDC," pegs worm infestation in the U.S. at about 10% of the population, mainly in children (link below). Candida yeast and gut bacterial overgrowth and the like are certainly more common.