Our ancestors had infections and parasites we don't, and even if to some extent we evolved to coexist with them, that doesn't mean we can just go back to that.

Our ancestors had infections and parasites we don't, and even if to some extent we evolved to coexist with them, that doesn't mean we can just go back to that. I know I read something about a "raw water" startup on HN in the relatively recent past. https://www.vox.com/science-and-health/2018/1/4/16846048/raw-water-trend-silicon-valley https://www.vox.com/science-and-health/2018/1/4/16846048/raw...