I think I remember reading somewhere that the reason the japanese have a better health expectancy than the americans is due to their omega3: omega6 ratio, higher 3:6. Where in american the omega6 is much higher than omega3.
I do know that both the Americans and Japanese are high up in the list for total hours worked. I know Americans are low in vacation time compared to Europe and such. Maybe one day they will eliminate sleep and we can all enjoy the joys of 16hr work days.