In Okinawa, Japan—home to one of the world’s oldest populations—a simple phrase often said before meals is more than a ritual. It’s a way of life. 'Hara hachi bu', meaning "belly 80 percent full", has been quietly influencing how generations eat, think, and live longer.
The term surged into wider awareness after the 2023 Netflix docu-series Live to 100: Secrets of the Blue Zones, where explorer Dan Buettner travels to regions known for exceptional longevity. In Okinawa, he observed this practice firsthand. “This idea teaches each Japanese generation that our portion size is small,” said Asako Miyashita in Women's Health report. She is a registered dietitian nutritionist (RDN) who grew up in Japan.
At its heart, ‘hara hachi bu’ is about moderation—not restriction. And its impact stretches beyond the plate.
Kaibara’s own life lent some proof to the theory. “He lived to be 83, which was rare in the Edo Period—the life expectancy was less than 50 years old,” Miyashita said.
Even today, many Okinawans still speak the phrase aloud before meals. Miyashita recalled her own family doing the same. It acts both as a blessing and a gentle reminder: listen to your body.
“By focusing on the flavours, textures, and aromas of the food, people may get more satisfaction from their meals,” Webb said. She finds herself more aware of what and how often she eats. That, in turn, makes dining feel richer—not restricted.
Importantly, the practice isn’t meant as a weight-loss tool. “'Hara hachi bu' is not a diet, but a lifestyle,” said Webb. “It encourages mindful eating and portion control without the need for strict calorie counting or eliminating certain food groups.”
Webb agrees. “Eating until you’re 80 percent full is associated with a lower risk of acid reflux, bloating, and gastrointestinal issues.” It also appears to help regulate blood sugar, as smaller meals reduce the risk of glucose spikes, a key concern for those managing insulin resistance.
Obesity prevalence is just 3 to 4 percent in Japan. In contrast, the UK’s rate stands at 25.9 percent, raising the risk of conditions like heart disease and type 2 diabetes.
In a 2021 study published in Frontiers in Neuroendocrinology, researchers found women are two to three times more likely to experience mood-related disorders. Practices like 'hara hachi bu' may offer a buffer by fostering a more intentional relationship with food.
A 2009 study in the Journal of the American College of Nutrition reported that incidence of breast, colon, and prostate cancer among Okinawans was about 50 percent lower than the rest of Japan. While more research is needed, the connection between moderation and longevity remains a strong one.
For those with a history of eating disorders, caution is key. “People with eating disorders have lower energy intake than that of people without, therefore, ‘hara hachi bu’ could be dangerous because their daily intake exponentially decreased,” Miyashita warned.
If you're unsure, both experts advise speaking with a healthcare provider before attempting the method.
Use smaller dishes to help your brain adjust to reduced portions. Begin meals with non-starchy vegetables and chew thoroughly—at least 15 times per bite.
Stop at a “six or seven” on the hunger scale. Check in with your body. Fullness signals take time. “It takes about 15 to 20 minutes for your stomach to signal your brain that you are full,” Webb explained.
Estimate 80 percent of your plate visually. If you’re still unsure, wait before reaching for seconds. “Wait 15-20 minutes before deciding to eat more,” said Webb.
For beginners, a food journal can be helpful. Record what you ate, how much, and how it made you feel. “Write without judgement and use it as a learning exercise,” said Miyashita. Over time, patterns emerge, and the practice may become second nature.
Ultimately, ‘hara hachi bu’ is about reconnecting with your body. Not in pursuit of perfection, but in the quiet act of listening—one bite at a time.
The term surged into wider awareness after the 2023 Netflix docu-series Live to 100: Secrets of the Blue Zones, where explorer Dan Buettner travels to regions known for exceptional longevity. In Okinawa, he observed this practice firsthand. “This idea teaches each Japanese generation that our portion size is small,” said Asako Miyashita in Women's Health report. She is a registered dietitian nutritionist (RDN) who grew up in Japan.
At its heart, ‘hara hachi bu’ is about moderation—not restriction. And its impact stretches beyond the plate.
300 Years of eating modestly
The origins of 'hara hachi bu' trace back to 1713. Japanese philosopher and botanist Ekiken Kaibara wrote about the concept in his book Yojokun: Life Lessons From A Samurai. The book introduced the idea of “hara hachi bun me”—to stop eating at 80 percent full—as part of a broader philosophy of self-healing and bodily awareness.Kaibara’s own life lent some proof to the theory. “He lived to be 83, which was rare in the Edo Period—the life expectancy was less than 50 years old,” Miyashita said.
Even today, many Okinawans still speak the phrase aloud before meals. Miyashita recalled her own family doing the same. It acts both as a blessing and a gentle reminder: listen to your body.
A slower, more satisfying way to eat
For those raised to finish every bite on the plate, the idea of leaving food behind might feel uncomfortable. But according to dietitian Kouka Webb, who was raised on this principle in Japan, 'hara hachi bu' can actually make meals more enjoyable.“By focusing on the flavours, textures, and aromas of the food, people may get more satisfaction from their meals,” Webb said. She finds herself more aware of what and how often she eats. That, in turn, makes dining feel richer—not restricted.
Importantly, the practice isn’t meant as a weight-loss tool. “'Hara hachi bu' is not a diet, but a lifestyle,” said Webb. “It encourages mindful eating and portion control without the need for strict calorie counting or eliminating certain food groups.”
Why does Hara hachi bu give you a break
Overeating places a strain on the body—digestively and hormonally. “When you eat until you’re 100 percent full (and beyond that), you slow down digestion, absorption, and metabolism,” Miyashita explained. This, she said, stresses organs like the pancreas, kidneys, liver, and intestines.Webb agrees. “Eating until you’re 80 percent full is associated with a lower risk of acid reflux, bloating, and gastrointestinal issues.” It also appears to help regulate blood sugar, as smaller meals reduce the risk of glucose spikes, a key concern for those managing insulin resistance.
Obesity prevalence is just 3 to 4 percent in Japan. In contrast, the UK’s rate stands at 25.9 percent, raising the risk of conditions like heart disease and type 2 diabetes.
How does 'Hara hachi bu' help?
Food isn’t just fuel. It’s emotional. And often, people eat beyond hunger—out of boredom, anxiety or habit. Webb notes, “'Hara hachi bu' can help distinguish between physical hunger and emotional eating.” Mindful eating, she said, can improve wellbeing and reduce stress.In a 2021 study published in Frontiers in Neuroendocrinology, researchers found women are two to three times more likely to experience mood-related disorders. Practices like 'hara hachi bu' may offer a buffer by fostering a more intentional relationship with food.
Can it lower chronic disease risk?
Evidence suggests it might. Okinawans who stick to traditional diets—including 'hara hachi bu'—have significantly lower rates of diseases like cancer, stroke, and heart disease. “Eating until 80 percent full is associated with a lower risk of chronic diseases,” said Webb.A 2009 study in the Journal of the American College of Nutrition reported that incidence of breast, colon, and prostate cancer among Okinawans was about 50 percent lower than the rest of Japan. While more research is needed, the connection between moderation and longevity remains a strong one.
Who should not practise this method?
Not everyone may benefit equally. Webb pointed out that “it can be difficult to gauge fullness levels, particularly for people who are not accustomed to mindful eating.” This can lead to eating too much—or too little.For those with a history of eating disorders, caution is key. “People with eating disorders have lower energy intake than that of people without, therefore, ‘hara hachi bu’ could be dangerous because their daily intake exponentially decreased,” Miyashita warned.
If you're unsure, both experts advise speaking with a healthcare provider before attempting the method.
Starting Gently: How to practise ‘Hara Hachi Bu’
Curious to give it a try? Webb and Miyashita recommend starting with your environment. “Choose a quiet place with minimal distractions,” said Webb. “Leave your computer or TV off to avoid further distraction,” added Miyashita.Use smaller dishes to help your brain adjust to reduced portions. Begin meals with non-starchy vegetables and chew thoroughly—at least 15 times per bite.
Stop at a “six or seven” on the hunger scale. Check in with your body. Fullness signals take time. “It takes about 15 to 20 minutes for your stomach to signal your brain that you are full,” Webb explained.
Estimate 80 percent of your plate visually. If you’re still unsure, wait before reaching for seconds. “Wait 15-20 minutes before deciding to eat more,” said Webb.
For beginners, a food journal can be helpful. Record what you ate, how much, and how it made you feel. “Write without judgement and use it as a learning exercise,” said Miyashita. Over time, patterns emerge, and the practice may become second nature.
Ultimately, ‘hara hachi bu’ is about reconnecting with your body. Not in pursuit of perfection, but in the quiet act of listening—one bite at a time.
