noun
eating until 80% full; moderate eating
A traditional Japanese dietary principle of stopping when you feel about 80% full, often used in health advice.
腹八分に医者いらず。
Eating in moderation keeps the doctor away.
健康のために、いつも腹八分を心がけている。
For my health, I always try to eat until I'm 80% full.
Compound of 腹 (stomach) and 八分 (80%). The phrase reflects the traditional Japanese concept of 'hara hachibu', eating until 80% full for health and longevity.