I have been wondering recently just how dangerous it really is to drink from an unpurified water source while /out in nature. Reading up online has just made things less clear: any health or brand related website will urge you to never even consider it while other places such as forums or websites with more anecdotal evidence suggest that its not as black and white as it seems. As such it only makes sense to bring the conversation here so that certified /outists can have their say.

What I mainly have in mind are small to medium sized rivers and mountain creeks, though feel free to go beyond that, and here is what I have garnered so far:
> The most problematic thing are parasites which are often present in such sources. Bacteria and viruses are easier to cope with.
> Some people argue it really is just a matter of if you are willing to take the gamble that nothing took a shit or is rooting dead in the water upstream.
> Slower moving moving rivers / creeks are safer to drink from as less sediment is suspended and possibly UV rays from the sun can filter the top layer.

I am also interested in how geographically contextual this might be. For example drinking from a creek at 1000m or lower versus at 3000m or higher, or being in X country versus Y country. I'm already convinced this is not some big conspiracy and that its actually mega safe to do as otherwise drinking water spring would not exist (free to use and safe). Finally, if you know any indicators or signs of a safer source do share.

Really does make you think how tf our prehistoric predecessors survived drinking exclusively this way.