Sushi, Ramen, tempura! Those people live the longest! But not in their world, LCHF is immortal technique! Haha!
anyway, its not about carbs. its about what goes into your food, your lifestyle.
japanese have one of the best beef, reason because they are grass fed.
even the milk and butter.. its so good.
most of their food doesnt have much seasoning, even if, they used tamari soya sauce which is better also.
their food outside are always served in small serving, small bowls, small burger (mos burger). even their mcdonald's burger are the same size as mos burger.
green tea with no sugar.
most of their interchange station, from circle line to south bound line, you have to walk a very very long distance to reach. the way things are built aid their citizens to exercise more.
even their smoking area are very very few. you cant smoke in public in japan. i think this point, deter people from even thinking to smoke.
carbs probably is just 1 small percentage of their overall meal. they eat carbs, but they dont have addition preservatives or sugar etc.