[Phoenix-D]

I can say right now that this is false. Why? Well, everyone knows that sweat stinks. It stinks not because of itself (though it does have some smell), but because of the bacteria that eat it. The skin itself is your primary defense against bacteria.

The oily feeling you get when not washing, BTW, comes from having a -lot- of oil on your skin. You always have some.

If that's not enough proof check the life expectancy before and after soap was introduced. There is a very big difference. That's not to say being excessive with it helps either; you do always have bacteria, mites, etc living on you. Killing them all off is a bad thing because it clears room for ones your immune system can't handle to come in.

The biggest difference with these people is probably that they live in small communties. Assuming everything else is equal a small community means less chance to get a disease from a random stranger on the street.