My research has shown me that people who have lived in the same ecological niche for 500-1000 years "adapt" physically and culturally to a diet and exercise regime that supports good health for that niche. Relatively rapid change in diet and exercise, unbalances their system and produces ill effects. They are right on the diet part but they also need to look at how much daily exercise a typical child and adult got 100 or more years ago and figure out how to get - grin - people moving again and not doing as so many of us do - watch tv and sit behind a computer instead of taking a walk or a run.