I've seen several peeps now describe why they're against both R/O & distilled H2O, at least without mineral replacement -- they tell how not only is distilled devoid of all healthy minerals, but it's also left 'hungry' to return to its 'natural state' of carrying said dissolved minerals, & thus in ur body it acts like a vacuum cleaner sucking up said minerals in ur blood/bones/organs etc!
In latter ~third of my 3 Baskets Living vid above, he explains this as why he uses vinegar + distilled H2O for the final reverse-flow-flush stage of his black filter cleaning routine! it's a vacuum cleaner as it pushes thru!
Mercola say as much here too; 15m:
https://www.youtube.com/watch?v=sHBbjtYt9D0