Eli5: How did native tribes drink from rives and streams without getting sick if they couldn’t boil the water?

Question

I know that the rives and streams had less man made pollutants, but what about parasites and such.

In: 4

Answer 1

Native tribes would get sick from bad water all the time. It was a fact of life. But they also understood where to get water that was less likely to make you sick.

Fast moving streams and water are less likely to contain parasites and pollutants and native tribes understood that.

There was also a lot less pollutants in the water ways than there are today

Anyone who’s drank well water for a while also understands that it makes you sick at first, but you get used to it after a while. Your gut builds up a tolerance to what’s in the water and you are less likely to get sick.