5 Healthy Japanese Food That Boost Your Immune System | CoolJapan

With COVID-19 spreading around the world, it's become more important than ever to keep your immune system strong and healthy. One of the ways to do this is to fortify your diet with immunity-boosting food. Take a cue from the Japanese diet, which is known to be among the healthiest in the world. Here are five staple ingredients in Japanese cuisine that you can add to your meals to supercharge your health and add spice to your dishes.


Probably the cornerstone of the Japanese diet, miso is a fermented paste made with a blend of soybeans, sea salt and rice koji (a type of mould used to ferment soybeans). There are more than 1,000 types of miso, with nuanced differences in texture, colour and flavour.

MisoMiso soup with spring onion. Image credit: Ponyo Sakana on Pexels

Its benefits: Rich in protein, miso is also chock-full of essential minerals such as various B vitamins (helps with cell metabolism), vitamins E (helps reduce damage caused by free radicals), and folic acid (helps produce and maintain new cells). As a fermented food, miso also promotes the production of good bacteria in your gut. Your gut is often known as your "second brain", and good gut health is important for overall mental and physical wellbeing.

How to enjoy it: While miso soup is probably the easiest and most obvious way of incorporating miso into your diet, you can also include miso in salad dressing or as a marinade for vegetable and tofu dishes. Just be careful not to boil your miso — heat that's higher than 60 degrees Celcius will kill the active bacteria present. But don't worry because even if you heat it up, it still contains minerals for your health benefits.


Sticky, slimy, stringy and with a smell that may not agree with everybody, natto is one ingredient that you either love or hate. Whichever side you're leaning on, you can't deny that this fermented soybean is extremely nutritious. 

Its benefits: Like miso, natto is fermented, which helps stimulate the growth of probiotics in your digestive system, enabling the better absorption of nutrients. Natto also has plenty of dietary fibre, which helps lower cholesterol levels and control your blood sugar level.


Maze soba with natto. Photo from: 8-Low Ural on Unsplash

How to enjoy it: Natto is best eaten in the morning — simply stir it with some soy sauce and mustard and enjoy with plain rice. If you’re not a fan of its pungent aroma, try adding a dollop to your miso soup and mix it in.


Although it's often translated to "pickled plums", umeboshi is actually made from ume, which is more of a cross between an apricot and a plum. Umeboshi has been a big part of the Japanese diet for centuries, and for good reason. Not only is the sweet-savoury condiment tasty, but it also comes with plenty of health benefits.

UmeboshiTray of umeboshi. Photo from: Richard Iwaki on Unsplash

Its benefits: Ume has a very high concentration of citric acid — in fact, it's higher than in any other fruit. Citric acid is known for its antibiotic and anti-inflammatory properties. Umeboshi also contains benzoic acid, which is believed to limit the growth of bacteria. This is why umeboshi is often incorporated in rice balls or bento boxes, as it helps keep the rice fresh for longer.

How to enjoy it: Despite its health benefits, the high salt content in umeboshi means you should probably limit yourself to just one or two a day (traditionally, umeboshi has about 20 per cent salt content). Apart from adding it to your rice balls or bento boxes, you can also try your hand at making umeboshi pastes or vinaigrettes.


This is a special type of green tea that is made from young tea leaves that have been grounded into a powder.

Its benefits: High in antioxidants, matcha also has high concentrations of magnesium, zinc, vitamin C (helps boost immunity and reduces your risk of chronic disease) and selenium (important for building a robust immune system).

Matcha DrinkMatcha drink. Photo from: Sarah Gualtieri on Unsplash

How to enjoy it: Matcha is best enjoyed whisked with hot water and drank as it is. If you like, you can also add a tiny bit of honey to sweeten the taste.


The yuzu fruit may be small but it sure is mighty. Often referred to as the Japanese grapefruit, this citrus fruit is a ubiquitous part of Japanese cuisine — featured in everything from salads to cocktails — and is packed with health benefits.


Yuzu. Photo from: Jirreaux on Pixabay

Its benefits: Yuzu contains high amounts of vitamin C, far more than lemons or oranges. Yuzu is also known for treating respiratory infections and boosting the immune system.

How to enjoy it: Because of its subtly sweet fragrance, the yuzu peel is often mixed with some honey and brewed into an aromatic tea. However, this versatile ingredient can also be used to add zest to salad dressings or marinades. You can also simply squeeze the juice and pour over ice.