How is nutrition taught in Japan – from a school perspective, what’s expected at home, etc?

As a North American, we always learn about “hara hachi bu” in Japan but don’t hear about anything else yet Japanese people live the longest and have quite good health overall. After visiting many years ago, I saw that a lot of fast food options or convenience store food isn’t terrible but it’s arguably as healthy as North American options. What kinds of things are taught about nutrition and healthy eating in Japan? Maybe we don’t see the full extent of healthy eating that happens in private homes.