We take cleanliness for granted in this modern age, and consider personal hygiene to be an integral part of civilized society, but the definition of acceptable cleanliness levels vary by culture and country.
Even though we can’t agree on the average number of times people should bathe in a week we can all agree that going without a bath for sixty years will make you one stinky human being!
Amou Haji doesn't adhere to societal norms in any way- he's over 80 years old (7 years older than the average Iranian lifespan), he smokes animal feces and drinks water out of a rusty oil tin, his favorite food is rotten porcupine, and he hasn't taken a bath in over 60 years because he believes bathing will make him sick.
Maybe Amou is on to something with his Bizarro health regimen? Nah, it's probably just the luck of the draw...