Hara hachi bu: Is it healthier to eat until you’re 80 per cent full?

Some of the world’s healthiest and longest-living people follow the practice of “hara hachi bu” – an eating philosophy rooted in moderation. This practice comes from a Japanese Confucian teaching, which instructs people to eat only until they are around 80 per cent full.

More recently, it has been gaining attention as a strategy for weight loss.

But while hara hachi bu might emphasise eating in moderation and stopping before you are full, it shouldn’t really be seen as a method of dietary restriction. Rather, it represents a way of eating that can help us learn to have awareness and gratitude while slowing down at mealtimes.

Research on hara hachi bu is limited. Previous studies have evaluated the overall dietary patterns of those living in regions where this eating philosophy is more commonplace, not the “80 per cent rule” in isolation.

However, the available evidence does suggest hara hachi bu can reduce total daily calorie intake.

It is associated with lower long-term weight gain and lower average body mass index. The practice aligns with healthier meal pattern choices in men, with participants choosing to eat more vegetables at mealtimes and fewer grains when following hara hachi bu.

Hara hachi bu shares many similar principles with the concepts of mindful eating or intuitive eating. These non-diet, awareness-based approaches encourage a stronger connection with internal hunger and satiety cues. Research shows both approaches can help reduce emotional eating and enhance overall diet quality.

Hara hachi bu may have many advantages that go beyond losing weight.

For instance, its focus on awareness and eating intuitively may offer a gentle and sustainable way of supporting long-term health changes. Sustainable health changes are far easier to maintain in the long term. This may improve health and prevent weight regain, which can be a risk for those who lose weight through traditional diet approaches.

The ethos of hara hachi bu makes perfect sense in the context of modern life and may help us develop a better relationship with the food we eat.

Evidence suggests that around 70 per cent of adults and children use digital devices while eating. This behaviour has been linked to higher calorie intake, lower fruit and vegetable intake and a greater incidence of disordered eating behaviours including binge eating and overeating.

As a dietitian, I see it all the time. We put food on a pedestal, obsess over it, talk about it, post about it – but so often, we don’t actually enjoy it. We have lost that sense of connection and appreciation.

Being more aware of the food we eat and taking time to taste, enjoy and truly experience it, as hara hachi bu emphasises, can allow us to reconnect with our bodies, support digestion and make more nourishing food choices.

Trying hara hachi bu

For those who want to try hara hachi bu or take a more mindful and intuitive approach to improve their relationship with food, here are a few tips:

1. Check in with your body before eating

Ask yourself, am I truly hungry? And if so, what kind of hunger is it – physical, emotional or just habitual? If you are physically hungry, denying yourself may only lead to stronger cravings or overeating later.

But if you are feeling bored, tired or stressed, take a moment to pause. Giving yourself time to reflect can help prevent food from becoming a default coping mechanism.

2. Eat without distractions

Step away from screens and give the meal your full attention. Screens often serve as a distraction from our fullness cues, which can lead to overeating.

3. Slow down and savour each bite

Eating should be a sensory and satisfying experience. Slowing down allows us to know when we are satiated and should stop eating.

4. Aim to feel comfortably full, not stuffed

If we think of being hungry as a one and being so full you need to lie down as a 10, then eating until you are around “80 per cent full” means you should feel comfortably satisfied rather than stuffed. Eating slowly and being attuned to your body’s signals will help you achieve this.

5. Share meals when you can

Connection and conversation are part of what makes food meaningful. Connection at meal times is human and a key to longevity.

6. Aim for nourishment

Ensure your meals are rich in vitamins, minerals, fibre and energy.

7. Practise self-compassion

There is no need to eat “perfectly”. The point of hara hachi bu is about being aware of your body, not about feeling guilty over what you are eating.

Importantly, hara hachi bu is not meant to be a restrictive eating approach. It promotes moderation and eating in tune with your body, not “eating less”.

When viewed as a means of losing weight, it risks triggering a harmful cycle of restriction, dysregulation and overeating – the very opposite of the balanced, intuitive ethos it is meant to embody. Focusing solely on eating less distracts from more important aspects of nutrition, such as dietary quality and eating essential nutrients.

This practice may not suit everyone. Athletes, children, seniors and those living with illness often have higher or more specific nutritional needs, so this eating pattern may not be suitable for them.

While often reduced to a simple “80 per cent full” guideline, hara hachi bu reflects a much broader principle of mindful moderation. At its core, it is about tuning into the body, honouring hunger without overindulgence and appreciating food as fuel – a timeless habit worth adopting.

This article was first published in

The Conversation.