SEOUL – Kimchi, Korea’s centuries-old fermented staple, has gained fresh global recognition after being named a “gut health” food in the
latest Dietary Guidelines for Americans
(2025–2030), issued by the US Department of Health and Human Services and the US Department of Agriculture.
In the new guidelines, kimchi is highlighted alongside foods such as sauerkraut, kefir and miso as a fermented food that helps support gut health by maintaining microbiome diversity.
The gut microbiome refers to the vast community of bacteria, viruses and other micro-organisms that live in the digestive tract. Research over the past decade has shown that a balanced and diverse microbiome does far more than aid digestion.
It plays a role in immune function, metabolism and even brain health, influencing how the body responds to stress and inflammation.
Fermented foods are increasingly valued because they help create an environment in which beneficial microbes can thrive. This is where kimchi stands out.
Kimchi is made by fermenting vegetables, most commonly napa cabbage and radish with garlic, chilli pepper, ginger and salted seafood. As fermentation begins, natural lactic acid bacteria multiply rapidly, lowering the pH and creating an acidic environment that favours beneficial microbes.
According to research from the World Institute of Kimchi, the number of lactic acid bacteria in kimchi can increase from around 100,000 per gram at the early stage of fermentation to more than 100 million per gram once fully matured.
Scientists have identified dozens of functional strains in kimchi, many linked to anti-inflammatory effects, metabolic health and immune support.
Kimchi also contains dietary fibre from vegetables. This fibre acts as “food” for gut bacteria, helping them produce beneficial compounds as they break it down.
Some studies suggest that fermented foods combining fibre and live microbes may influence the microbiome more effectively than fibre or probiotics alone.
Emerging studies indicate that certain lactic acid bacteria found in kimchi may also help regulate inflammation and oxidative stress. Because chronic inflammation is linked to conditions ranging from obesity to neurodegenerative disease, this has drawn growing scientific interest.
The gut-brain connection is another area of attention. Specific gut microbes are known to interact with stress hormones and neural signalling pathways, reinforcing the idea that gut health can affect mood and mental well-being.
Kimchi’s health benefits are closely tied to its history.
Long before refrigeration, Koreans developed fermentation as a way to preserve vegetables through harsh winters. Over time, kimchi evolved into hundreds of regional varieties, reflecting local ingredients, climates and tastes.
In 2013, the communal practice of making kimchi, known as kimjang, was recognised by UNESCO as an Intangible Cultural Heritage.
Despite its benefits, kimchi is a salted food and can be high in sodium. Experts emphasise balance rather than excess, especially for people sensitive to salt.
Still, for those whose diets rely heavily on processed foods and lack fibre, adding moderate amounts of kimchi can be a simple way to support gut health. THE KOREA HERALD/ASIA NEWS NETWORK