Just to clarify, I am talking about natural exercise and natural non-stress :) In their small communities you get stress and excrete it, while in the average larger community you accumulate it. It is the background "stress radiation", low intensity nagging stress, that does all kinds of nasty things to us - more accurately, we do it to ourselves and each other. Similarly, I would not equate time in the gym or jogging in Manhattan to their exercise.
I don't know if by some fluke they have the perfect 3-6 ratio in their diets, but if you get your fresh food and exercise (and those beneficial worms ;) ), it does not matter.
Judging from other "natives" I met, probably as much as they can(with Walmart being 1000 miles away, that would be little). I don't know if you were thinking in terms of "incriminating" veg oil in favor of butter etc, which is the trend in Atkins etc, but the takeaway message of such studies is exercise and the stress-free life, you become what you do and what you think! Eating is a part of thinking and doing, but only up to a point.
I don't know if by some fluke they have the perfect 3-6 ratio in their diets, but if you get your fresh food and exercise (and those beneficial worms ;) ), it does not matter.