Being nude is normal in many cultures, not surprisingly, mostly in tropical regions. Hot and humid climate discourages clothes. Amazon Indians are a prime example, but primordial naturism is everywhere.
Goran Šafarek is a world traveler and river expert. He has encountered many such cases during his voyages. You can read more on his blog. Here, he will write more about being nude in the jungle.
The state of nude is natural to many native people around the world. The clothes are welcomed as a protection against the cold and other elements, including insects, it could also be cumbersome. But, even in civilized place, I have witnessed that being naked is nothing to be ashamed.
I remember paddling on a wild river in west Madagascar. After a hard day on the river, scorched by the sun in our wooden canoe, we have finally landed on a nice sandy beach. It is almost savannah, with scattered trees and lots of tall grasslands. The clouds were already red and yellow from the setting sun.
As we were pitching the camp, the people from the nearby village came. They were clearly peasants, poor, but proud. They greeted us and we greeted them. Older women started washing the clothes and dishes, while a group of young girls entered to take a bath. They were around 16, maybe older, it was difficult to guess. They were totally naked, not more than ten meters in front of us, vazaha, and in front of their parents and other adults. Their slender, wet bodies glistening on the red sun were darker than the milky brown river.
I was astonished by their beauty, but more with the confidence and the total absence of the shame. Such a scene is literally unthinkable in a western society. Ok, besides nude beaches and camps. This scene was so warm, not only from the pleasant evening and warm tones from the sunset. It was the scene of harmony with nature
I saw many times naked children happily swimming into the river –, not only from Madagascar but also from Asia, Africa, Latin America. It is a natural way, the human body in the water is so harmonious, liberating with nothing sexual in it.