LESSON TWO: HARA HACHI BU Painlessly cut calories by 20 percent If you’re ever lucky enough to eat with Okinawan elders, you’ll invariably hear them intone this Confucian-inspired adage before eating: hara hachi bu—a reminder to stop eating when their stomachs are 80 percent full. Even today, their average daily intake is only about 1,900 calories (Sardinians traditionally ate a similarly lean diet of about 2,000 calories a day).