Is faster absorption really that big of a deal? Highly developed countries like Japan and South Korea that eat a lot of white rice seem considerably healthier t

Is faster absorption really that big of a deal? Highly developed countries like Japan and South Korea that eat a lot of white rice seem considerably healthier than the U.S. as an example. I don’t really know much about this topic but I always assumed additives were a much greater problem than white rice, white bread, etc.