Miso Adds More Than Just Flavor: Benefits for Your Heart, Gut, and Body
Key takeaways:
Miso is a fermented soybean paste that has been used for centuries in Asian cuisine. It adds a complex savory flavor to soups, dressings, and marinades.
The fermentation process used to make miso makes it easier to digest and increases the absorption of its many nutrients.
Fermentation also increases the isoflavone content. This may provide health benefits, like reduced risk of heart disease, lower blood pressure, and reduced risk of some types of cancer.
Miso is a traditional Japanese condiment used for centuries throughout Asian countries. It enhances the flavor and savoriness (or umami) of many dishes. It’s most often associated with miso soup, but it’s also commonly used in dressings, sauces, marinades, and even desserts.
As experts have discovered more about the health benefits of fermented foods, miso has gained popularity. So, if you’re thinking about giving it a try, we’ll explain how it can be good for both your taste buds and your body.
What is miso?
Miso is a paste that’s made from fermented soybeans. People use it to add flavor and depth to recipes. It’s most commonly used in Asian recipes, like the classic miso soup. But it’s becoming more common in many different dishes, given its impact on flavor and potential health benefits.
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To make miso, an enzyme (the koji enzyme) is combined with rice or barley and allowed to ferment. The enzyme converts the rice or barley starch to sugar. This fermented koji starch is then combined with mashed soybeans, salt, and water. The mixture is sealed and stored while it undergoes a second fermentation.
There are three main types of miso with different flavor profiles:
White miso has a mild, slightly sweet, and salty flavor.
Yellow miso has a deeper and very salty flavor.
Red miso has the strongest, saltiest flavor.
Miso’s color is determined by the starch used to make it and how long it ferments. In general, the deeper the color, the stronger the flavor.
Health benefits of fermented foods: Miso is not the only fermented food that’s good for your gut and heart. Yogurt, pickled vegetables, and tofu are fermented, too.
The myths around soy: Some people think soy behaves like estrogen in the body. But the latest research tells a different story.
Gut-friendly foods: Miso is on the list of the nine best foods that help boost your gut health.
What are the health benefits of miso?
There are areas of the world — called blue zones — where people tend to live very long and healthy lives. One of these areas is Okinawa, Japan. Along with a diet rich in vegetables and fish, people in Okinawa commonly consume miso soup. So, researchers have wondered whether their increased longevity could be partly due to the consumption of miso.
This means there’s a good amount of observational research on people who consume more miso than others. There are fewer clinical trials on miso itself. But still, there are a few studies that indicate miso may help improve some chronic health conditions.
Gastrointestinal conditions and symptoms
When it comes to soy products and miso, there’s some evidence that the probiotics and isoflavones may help support gastrointestinal (GI) health.
The fermentation process used to make miso increases the digestibility of soybeans because it increases its probiotic content. It also may increase its isoflavone content. This helps strengthen the lining of the GI tract, boost the immune system, and lower the risk of developing some inflammatory diseases.
Some research also suggests that a diet rich in probiotics may help reduce intestinal inflammation, possibly reducing the symptoms of inflammatory bowel disease.
One large study in Japan found that people who drank miso soup daily had significantly fewer cases of gastroesophageal reflux (GERD) and indigestion. Another found that increased intake of soy products significantly reduced blood markers of inflammation in postmenopausal women, which indicates reduced inflammation throughout the body.
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Heart disease
Soy-based foods, including miso, contain a variety of nutrients that may help reduce the risk of heart disease and strokes.
Foods rich in soy have been shown to help lower cholesterol and triglyceride levels in some people. This led the FDA, in 1999, to support the claim that consuming soy protein daily may help reduce the risk of heart disease. Shortly afterward, the American Heart Association recommended people eat soy protein daily to help reduce the risk of cardiovascular disease .
Studies have shown that people who eat more foods rich in soy protein have lower low-density lipoprotein cholesterol (LDL) cholesterol levels. One large meta-analysis found that consuming 25 g of soy protein a day reduced LDL cholesterol levels by 3% to 4% in adults. Similar results have been seen with diets supplemented with soy isoflavones.
Miso contains the isoflavones, plant sterols, and vitamin E found in other types of soy protein. But it contains a minimal amount of soy protein overall. The research on miso’s specific effects on blood lipid levels is less clear, but some evidence suggests regular consumption may have a protective effect.
Blood pressure
Miso soup can have a high salt content, which isn’t always good for blood pressure. However, research suggests that miso may lessen the effects of salt on blood pressure.
One small study comparing miso soup to a non-salted soy product found a significant reduction in nighttime blood pressure in those consuming miso compared to the non-miso group. Daytime blood pressure wasn’t impacted, but it’s not clear why.
Can miso reduce the risk of certain cancers?
Consuming miso may lower the risk of certain cancers due to its abundance of isoflavones. These compounds are believed to have a protective effect against some cancers.
One large meta-analysis found that a high intake of soy isoflavones reduced overall cancer risk by 6% compared to the lowest intake. The most significant impact was on the risk of lung cancer, which was 15% lower in those with the highest intake of soy isoflavones.
The soy isoflavones in miso have also been attributed to lowering the risk of breast cancer. In a large study with Japanese women, those who had miso soup daily had a 54% lower risk of developing breast cancer compared to those who rarely consumed it or had it a few times a week.
How much miso should you eat?
A lot of the research on miso shows benefits in people who consume it every day. The traditional Okinawan diet has received considerable attention for its association with longevity and fewer age-related diseases.
People who follow this diet have a bowl of miso soup before each meal, along with fruits and vegetables, fish, and legumes. They also commonly use miso as a seasoning for other foods.
If you’re new to using miso and want to explore its nutritional benefits, here are a few simple tips:
Start with white miso paste. This will have the mildest flavor.
Add just a teaspoon or two at a time to your recipes.
Since miso is salty, hold off on adding any salt to the dish until you taste it first.
If you’re using it in hot food, add miso toward the end of the cooking process. Heating miso will diminish the available amount of bacteria that’s good for your gut.
Here are a few ways to use miso in specific foods:
Soup: Stir a tablespoon or two of miso paste into water or unsalted vegetable broth to make a quick miso soup. Add your favorite vegetables, proteins, and herbs.
Casseroles: Mix a teaspoon or two with the sauce you are using to increase the savory flavor of the dish.
Salad dressing: Blend miso paste with olive or grapeseed oil, vinegar, honey or sugar, and fresh herbs for a delicious dressing. You won’t need to add salt to this as the miso is salty enough.
Marinades: Mix a teaspoon or two with soy sauce, vegetable oil, garlic, minced onion, and ginger for an Asian-inspired marinade. This works well with heartier proteins like chicken, beef, or tofu.
Smoothies: Miso is a nice addition to a green smoothie. Just a little will add an extra depth of flavor.
The bottom line
Miso is a versatile and nutritious ingredient that adds a surprising amount of flavor to your meals. The fermentation process used to make miso adds bacteria that’s good for gut health and digestion. And research suggests that people who consume it frequently have lower rates of heart disease and some cancers. Consider adding a bowl of miso soup to your daily routine or stirring a teaspoon into your morning smoothie or salad dressing.
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References
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