I had wondered about that in some of the earlier shows. There was one in which nobody had drinking water until they were able to make fire and boil the water to decontaminate it. One of the contestants was so afraid of becoming dehydrated that she drank the contaminated water. (With no apparent ill effect it seems.)
But excessive food deprivation for people of normal weight and dehydration for anybody can have serious effects on one's health. And apparently they were't allowed to catch and eat the crabs and other sea creatures????? There are some 'rules of the game' that apparently are never brought up.
I can't recall a show in which they weren't allowed to fish, if fishable water was available. I do recall one island that had lots of snakes, but they weren't allowed to kill and eat them. Then there was the pig in Season 2!
