Hara Hachi Bu is a saying from Okinawa in Southern Japan that advises people to stop eating when they're 80% full. Okinawa is famous for the longevity of the people who live there.
I learned it from Michael Pollan's excellent book Food Rules many years ago. He shares traditions, including the Ayurvedic in India, the Chinese, and the prophet Muhammad, that all counsel stopping eating earlier than your stomach might be telling you. That, and the German expression, "You need to tie off the sack before it gets completely full."
Hara hachi bu also appears in Dan Buettner's Netflix documentary Live to 100: Secrets of the Blue Zones. Blue Zones are areas in the world with the longest lifespans. Dan Buettner identifies eating to no more than 80% full as one potential factor in Okinawans' long lives.
The more literal translation of hara hachi bu is stomach eight parts (out of ten).
Some other methods to eat less without sacrificing enjoyment include:
Also see:
It's sometimes misspelled hari hachi bu or said as hara hachi bun me.