The Okinawan diet is also famous for being a calorie restricted diet. There is a famous saying there that roughly translates to "eat until you are 80% full".

Source: https://en.wikipedia.org/wiki/Hara_hachi_bun_me

I'm actually surprised that Wikipedia says they consume 1800 calories a day. When I am doing intermittent fasting I am around 1400-1600.