They also died rather young, on average.
But in all seriousness.
Us middle-upper class westerners, we're coddled through childhood, by parents who have this strange idea that their children shouldn't go through any of the hardships they went through. God forbid making your child do some chores around the house, most parents have trouble even asking their child to make his/her bed each morning, let alone do an hour of daily chores... We're brought up as mental midgets, to crumble at the first sign of serious obstacles in our path, and real challenges and real exertion exhaust us to the point where we require shit like energy drinks as a crutch to keep us going.