For centuries, Japanese food culture has embraced a simple philosophy: health is built through everyday habits rather than quick fixes. Long before the concepts of gut health, probiotics and personalised nutrition came along, Japanese households were already incorporating fermented foods such as miso, kōji, soy sauce, nukazuke (rice bran pickles) and natto into their daily meals.
Today, modern science is beginning to explain why these traditions have endured. By 2026 and 2027, the growing adoption of gut microbiome testing is expected to usher in a new era of personalised wellness in Japan. Rather than following the latest food trends, more people are likely to choose foods based on their own microbiome profiles and individual health needs. In many cases, this journey will naturally lead people back to traditional fermented foods, not out of nostalgia, but because they support a personalised Japanese diet tailored to each person’s unique microbial balance. In doing so, cutting-edge science may reaffirm wisdom that has shaped Japanese food culture for more than a thousand years.
This connection between tradition and modern health reflects a broader philosophy that has long existed in Japan. When people think of the secrets to a long and healthy life, they often imagine revolutionary diets or exotic superfoods. Yet Japanese culture has always placed greater value on small, sustainable habits that become part of everyday life.
One of the best-known examples is the proverb Hara hachi-bun me ni isha irazu”Eat until you’re 80% full, and you’ll have no need for a doctor” Rather than eating until completely full, this practice encourages stopping just before satiety, recognising that the brain needs time to register fullness. It is a simple approach that naturally helps prevent overeating.
Another enduring principle is Ishoku Dōgen, meaning “food and medicine share the same source.” Instead of relying solely on treatment after illness develops, this philosophy emphasises maintaining health through daily nutrition. Fermented foods such as natto, miso, kōji and nukazuke are not viewed as functional foods or wellness products, they are simply familiar ingredients that have formed the foundation of Japanese meals for many years.
Other aspects of Japanese wellbeing follow the same practical philosophy. Proverbs encouraging early sleep and regular waking, the belief that emotional wellbeing influences physical health, the daily practice of Radio Taisō callisthenics, the relaxing habit of soaking in a hot bath, and Japan’s strong culture of annual health check-ups all share a common theme that prevention is more valuable than cure. These day-to-day routines may appear ordinary, but it’s the consistency of them which makes them effective.
Among Japan’s traditional fermented foods, natto is starting to attract increasing international attention as interest in gut health continues to grow. Yet despite being a staple in Japan for centuries, it has taken, and still is taking, a long time to gain wider acceptance in Western markets.
Natto’s distinct flavour and smell can put off first-time eaters, as from the look and smell of it, many form negative impressions which are hard to change, even once they have tried it. Natto, however, is now being recognised within the broader context of microbiome health, with its unique blend of probiotics and prebiotics, containing live beneficial bacteria from Bacillus subtilis var. natto and retaining dietary fibre, making it a symbiotic food that supports gut health.
As a living fermented food, though, distributing natto is complicated, as it requires a consistent frozen or refrigerated supply chain to maintain quality. That’s why I am now involved with premium natto supplements, made from the highest quality natto, but powdered into small capsules. This enables those who don’t want to sample the raw form of natto to still reap its benefits, but instead of eating it during breakfast, it can be taken as part of a day-to-day routine, just like many other fermented foods available and eaten heavily in the Western world, such as yoghurt and kefir.
As personalised nutrition continues to change, the future of wellness looks to be rediscovering traditional foods and those that have been used through generations for their health benefits. Looking at these traditional foods through modern-day science and technology is helping us transform ancient food traditions and bring them into the modern market.
