An Introduction to Miso: Health Benefits and Uses
When you think of miso, you may be reminded of the last time you indulged in a bento box and a few California rolls. But miso is far more than just a pre-sushi soup appetizer. Although this superfood isn’t as commonly used in Western cooking as it is in China or Japan, miso paste has some pretty impressive health benefits (plus a satisfying savory taste) that may leave you wondering why you haven’t picked up your own container sooner.
What Is Miso and How Is It Made?
Miso is a Japanese word that translates to “fermented beans.” It’s essentially soybean paste, which is made by fermenting soybeans with grains (such as rice, barley or buckwheat), salt, and koji, a type of yeast produced by a fungus called Aspergillus oryzae.
At first, picturing yourself eating a food made from fungus may not seem appetizing. But rest assured, Aspergillus oryzae is a type of fungus your body will appreciate. In fact, some even call it “magical mold.” This is because when fermented to make koji, Aspergillus oryzae produces a number of enzymes that aid in digestion and support gut health. (1) If you’ve ever wondered if there’s a benefit to having miso before meals—and why it’s commonly served in the morning in Japan—this is part of the reason.
Miso is known to be high in sodium, but research shows that it doesn’t have the same negative impact on the cardiovascular system as table salt does, presumably due to the fermentation process. (2) One study showed that long-term consumption of miso was actually able to help lower salt-induced hypertension over time. (3)
What Are the Different Types of Miso?
There are many different colors and types of miso, and classifying them can be a little tricky, but don’t let the options intimidate you. Miso is typically classified based on the type of grain it’s fermented with, such as rice (kome miso) or barley (mugi miso), or a mixture of both (awase miso). Some miso is fermented only with soybeans. These are just a few examples.
All types of miso can also range in color—from white, red, yellow to dark chocolate brown—depending on how long it’s fermented for, which can be anywhere from three months to three years. The general rule of thumb is the darker the miso, the richer and “fuller bodied” it is; it will be saltier and more savory.
For example, white miso is fermented for the shortest length of time (usually less than a year), which is why it tends to be on the sweeter side, making it a great addition to enhance the flavor of salad dressings, sauces, and other condiments like mayo.
You could even use white miso to sweeten desserts, such as brownies, pies, and homemade ice cream. If you’re a little skeptical, jump on Pinterest and type in miso dessert recipes. Prepare to be amazed!
As most miso experts seem to agree, don’t stress too much about the type of miso you buy. If you opt for a darker (and saltier) version, you can simply reduce the amount you use to achieve a balanced flavor in your recipes. Making miso soup? Any type of miso can be used for that. All varieties of miso will provide you with the same health benefits.
If you follow a gluten-free diet, be sure to read miso labels, since some varieties of miso are fermented with gluten-containing grains (such as barley).
Health Benefits of Miso
1. It’s good for your gut.
As you may know, the key to a healthy gut is eating plenty of fermented foods.
Not only is miso considered a gut-healing food thanks to the digestive enzymes it contains, but as a fermented food, unpasteurized miso also contains probiotic cultures, which can help improve chronic conditions such as leaky gut, candida, and gut dysbiosis. (Perhaps a nice change from your usual yogurt or sauerkraut.)
The longer the fermentation time, the more probiotics the miso will contain. For optimal gut-healing benefits, choose a miso paste that’s been fermented for at least six months (yellow or red kome miso will do just fine).
2. It’s a powerful anti-inflammatory food.
Chronic inflammation impairs your body’s natural healing processes, and when left untreated, it can lead to chronic illness and disease, such as cardiovascular disease, autoimmune conditions, and inflammatory bowel diseases (IBD). (4)
One of the most effective ways to prevent and address chronic inflammation is by regularly including anti-inflammatory foods your diet—and miso soup happens to be one of them. Miso is rich in soyasaponins, a type of antioxidant shown to reduce inflammation and lower cholesterol and blood glucose levels. (5) Soyasaponins are also known for having anti-tumor effects and may protect against various forms of cancer.
Long-term matured miso is richer in soyasaponins than all other soy products with the exception of tofu. (6)
3. It may help reduce the risk of certain female cancers.
Multiple studies suggest that regularly consuming miso soup may help reduce the risk of female cancers, such as breast cancer. (7)(8) This is due to the isoflavones found in soy which, like soyasaponins, have antioxidant activity. (9)
A half cup of miso soup is said to contain close to 60 milligrams of isoflavones, whereas soy milk contains only 10-20 milligrams per cup.
4. It contains trace minerals, electrolytes, and essential vitamins.
Aside from probiotics and antioxidants, miso also contains essential nutrients such as B vitamins, vitamin K, copper, manganese, iron, and selenium, as well as electrolytes such as magnesium and phosphorus. Do you know what this means? Yes, miso soup can make a great hangover cure or post-workout meal. (Just make sure to also consume a good amount of water, due to the high sodium content.)
5. It helps boost immunity.
Since 80% of immune system cells are found in your gut, foods that contain probiotics, such as miso, are crucial for strengthening immunity. (10) The essential vitamins and minerals in miso also provide an immune system boost. In fact, not only is gut health directly linked to your immune system, but it also influences your skin (known as the gut-skin axis) and your brain (the gut-brain axis). This means miso soup may also promote healthy skin and improved cognitive function.
The #1 Mistake When Using Miso
Probiotics are delicate nutrients that can be destroyed at high temperatures. Since these healthy bacteria are one of the most valuable health benefits of miso, you’ll want to avoid boiling it to keep the probiotics (and enzymes) intact.
Don’t worry: you can still make miso soup. After all, this soup isn’t known for being served cold! Just be sure to stir in your miso paste during the simmer time, rather than when the soup is boiling.
Wait… Isn’t Soy Bad for You?
Soy is one of the most controversial health topics. This is largely because nearly 95% of the soy crops grown in America are genetically modified (GMO), which some studies suggest may increase your risk of developing antibiotic resistance, allergies, and cancer. (11)(12)
However, this refers mostly to soy products that haven’t been fermented, such as tofu and soy milk. Unfermented soy products also contain phytates, which are known as “anti-nutrients” because they reduce your absorption of essential minerals. (13)
Fermented soy products are a bit of a different story. Not only does fermentation improve the digestibility of any food (especially soy products), but it also creates an entirely different nutrient profile, which includes probiotics and bioavailable essential vitamins and minerals.
So, you could say miso—as well as tempeh and natto, the other forms of fermented soybeans—are the exceptions to the “rule.” Otherwise, it’s ideal to consume unfermented soy products in moderation. (Don’t worry, a few cubes of tofu in your miso soup isn’t the end of the world.)
How to Make a Simple Japanese Miso Soup
Now that you’re well versed in miso’s health benefits, are you ready to give your own homemade, gut-healing miso soup a whirl? Here’s a traditional miso soup recipe you can make in under ten minutes. Use it as a base to make a miso ramen, or a colorful vegetable soup… or just sip on it and enjoy as is.
Simple Japanese Miso Soup
Here's a traditional miso soup recipe you can make in under ten minutes. Use it as a base to make a miso ramen, or a colorful vegetable soup... or just sip on it and enjoy as is.
- 4 cups water
- 1/2 cup green onion chopped
- 3 tbsp miso paste
- 1 sheet nori cut into squares
- 1/4 cup organic firm tofu cubed (optional)
Place water in a medium saucepan and bring to a simmer.
Add nori and simmer for 7 minutes.
While nori is simmering, place miso into a small bowl, add warm (not boiling) water and whisk until dissolved and a smooth liquid has formed.
Add miso to the soup and stir.
Add green onion and tofu (if using) to the pot and cook for roughly another 5 minutes.
Serve warm and enjoy.