Want to live a long, healthy life? This Japanese diet philosophy may hold the key
By Ella Nunn
With its high life expectancy and low obesity rates, there’s a lot we can learn from Japan. It’s the land of tofu, sushi and green tea, and its diet is renowned for supporting longevity and weight management. Plus, recent research conducted at the Japan Institute for Health Security (published this year) shows that those who eat traditional Japanese foods are likely to be happier than those who follow a Western diet.
“It’s a very balanced diet with small amounts of carbohydrates, sugar and salt, alongside good sources of meat, fish and vegetables,” says Reiko Hashimoto, the founder of Hashi Cooking, a Japanese cookery school in London. “Whilst sushi is the national dish, we actually eat a massive variety of food in Japan – from katsu pork to fresh vegetable pancakes. I think it’s this variety, plus the habits we grow up with, which makes our diet so healthy and happy.”
So, what health lessons can we learn from the Japanese diet?
The Japanese diet relies on oily fish, smaller portions and the philosophy of “hara hachi bu” or eating until you are 80 per cent full, all of which are linked to longer, healthier lives.Credit: iStock
Include fermented vegetables in salads
The Japanese diet is rich in fermented foods – ranging from pickles and sauces to pastes and drinks. Miso paste – an umami (rich, meaty and savoury) seasoning made from fermented soybeans – is a key ingredient in soups, ramen, and fish and meat dishes, while soy sauce is a staple in many meals.
“Fermented foods contain probiotics which are beneficial bacteria for the gut microbiome. They boost the diversity of your gut microbes, and the more diverse your gut microbiome, the better your immune system,” says Nichola Ludlam-Raine, a registered dietitian and author of How Not to Eat Ultra-Processed. “They have the potential to boost your mental health via the gut-brain axis too.”
In one 2025 review in Mental Health Research, 88 healthy volunteers were given probiotics and the researchers found they had the potential to reduce negative mood after just two weeks.
Ludlam-Raine suggests boosting your fermented food intake by adding kefir to your breakfast, or sauerkraut or kimchi to your salads.
Eat more oily fish
“It’s very uncommon to find a Japanese person that doesn’t like seafood or fish. It’s such a large part of the cuisine and culture,” says Victoria Lindsay, a registered dietitian who worked in London and now lives and works in Tokyo. “Plus it’s an island country, so the seafood is fresh and there’s a large variety on offer.”
Salmon and mackerel are particularly popular. “They’re a great source of lean protein and also rich in omega-3 fatty acids which are good for the heart,” Lindsay says. “It’s great to alternate between these oily fish and more traditional protein sources like chicken, beef and pork.”
Numerous studies have found that omega-3 fatty acids help to alleviate elevated cholesterol levels and high blood pressure, thereby reducing the risk of heart disease. Meanwhile, in several studies, their anti-inflammatory action has been shown to help protect the joints of people with rheumatoid arthritis.
Add tofu to your meat dishes
“In [the West], soy-based foods are seen primarily as an alternative to meat and are rarely consumed by meat-eaters. Yet in Japan, soy-based foods and meats are often mixed together,” Lindsay says.
Tofu and edamame beans (two popular Japanese soy foods) are both great sources of plant-based protein. A 100g serving of tofu contains about 12g of protein, while the same helping of edamame beans contains almost 15g.
Research shows that plant-based protein may be better for the heart than animal protein, especially that from processed red meat. A 2016 study compared animal and plant protein intake and found that those who ate more animal protein had a higher risk of cardiovascular mortality. Meanwhile, in 2020, researchers analysed data from more than 20,000 men and women in the US and found that, over a 20-year period, those who ate the most tofu and other soy products had the lowest risk of heart disease.
If you’re interested in adding more soy to your diet, Ludlam-Raine suggests adding tofu to your curries and stir fries, edamame beans to salads, or miso paste (made from fermented soy beans) to your winter soups.
Tofu is a common, versatile ingredient in Japanese cuisine and a great source of plant-based protein.Credit: Yuuji
Swap your daily coffee for green tea
Green tea is deeply ingrained in Japanese culture. The vast majority of people drink it regularly – including children, Lindsay says.
“At my daughter’s nursery, it’s very common for children to be given small amounts of unsweetened caffeine-free tea from around nine months old,” she explains.
In the West, we’re prone to enriching our cups of coffee or English breakfast with milk, sugar, sweetener and flavourings. However, Japanese green tea is often drunk as it is.
“Obviously, the key benefit of this is that you’re consuming drinks without any added sugar,” Lindsay says. “Green tea is also really high in antioxidants, especially catechins, which have anti-inflammatory effects.”
One 2022 study found that drinking green tea may benefit cognition, mood and brain function, while a review from the same year investigated its ability to boost metabolism for inactive people when paired with aerobic exercise.
If you can’t stomach a mug of plain green tea, Ludlam-Raine advises trying a lemon green tea or another more palatable variety.
Season your meals with ginger
Ginger is one of Japan’s most popular spices, alongside pepper and wasabi. It’s a staple in both savoury and sweet dishes – often added to rice bowls, gyoza dumplings and fish dishes.
“It has renowned anti-inflammatory and anti-nausea properties,” Ludlam-Raine says. These powerful effects are down to gingerol, the main bioactive compound in ginger. It has been shown to reduce morning sickness, boost digestive function, and possibly help to reduce cancer risk, due to its various anti-inflammatory and antioxidant compounds.
“I don’t tend to recommend taking ginger capsules,” Ludlam-Raine says, “but you can add ginger to all sorts of meals, including porridge, overnight oats, salad dressings, smoothies and soups.”
Bolster your meals with mushrooms
Mushrooms are a staple ingredient in Japanese cuisine. Earthy and meaty shiitake mushrooms are among the most popular, while the delicate and crunchy enoki varieties are used in a range of dishes.
“Variety is key because most mushrooms are a great source of fibre and B vitamins, but each one has a slightly different nutritional profile. The key is including them all in your diet and eating them regularly,” Ludlam-Raine says. Because of their beta-glucan content, they can boost the immune system and may even promote longevity, according to a large population study conducted in 2021.
“Consider adding whole mushrooms to your stir fries, stews, and even to your breakfast. They’re great on avocado toast,” Ludlam-Raine says.
Mushrooms not only add flavour and complexity to meals but they are a great source of fibre and B vitamins. The key is variety.Credit:
Swap biscuits and chocolate for rice crackers
While Japanese people are partial to sweet snacks such as mochi (chewy rice cakes filled with a sweet paste) and KitKats, they have a “lower threshold for sweet foods and added sugars”, says Lindsay. In fact, she recalls her Japanese friend telling her that it’s a huge compliment if you serve someone a dessert and they say: “That’s delicious and it isn’t too sweet”.
While Japanese children enjoy a sweet treat, it’s less common to give them biscuits, crisps or chocolate, and to feed them rice crackers instead, Lindsay says.
We know our penchant for sweet snacks is damaging for our health, with countless studies linking sugary foods to increased weight and adverse cardiovascular and metabolic outcomes. It may be worth occasionally swapping out your afternoon chocolate bar for a few rice crackers.
Eat until you’re 80 per cent full
“Hara hachi bu” is a traditional Japanese practice where people stop eating when they’re 80 per cent full. It encourages “intuitive eating, which helps you tune into your body’s hunger and satiety signals”, Lindsay says.
Ludlam-Raine adds: “We know that it takes around 20 minutes for the brain to realise that it’s full, so by eating mindfully in this way, you’re less likely to overeat.”
In Okinawa – a Japanese island where the philosophy originated – residents have far fewer age-related illnesses such as diabetes, heart disease and cancer, a 2024 study found. While more research is needed to confirm whether hara hachi bu is the sole driver behind such health outcomes, it’s notable that many residents who practise it tend to have lower rates of disease.
Serve smaller portions
“In restaurants, particularly when you’re outside of the major tourist areas in Japan, you’ll notice immediately that portion sizes are significantly smaller,” Lindsay says. “Obviously smaller portion sizes directly lead to consuming fewer calories. This is key – especially when people aren’t listening to their internal hunger and satiety cues very well and are just trying to eat all the food on their plate.”
Serving smaller portion sizes, coupled with the philosophy of “hara hachi bu”, means that Japanese people are more in tune with their hunger cues and tend to eat fewer calories a day as a result.
The Telegraph, London
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