Natto – Nutrition, Health Benefits and Side Effects

The fermented form of soybeans is natto. Interestingly, it is a dark, sticky mixture with a peculiar fragrance comparable to a pungent cheese. People commonly enjoy it as a morning dish. The pungent flavour is earthy, nutty, and slightly bitter. It is a famous cuisine in Japan. But, currently, it is gaining popularity in the United States and other western countries due to its health benefits.

Its health benefits and nutritional properties make it a superfood. Out of the several health benefits, the most significant health benefit is improving digestive health. However, natto’s influence on general health and wellness still requires a lot of research.

The HealthifyMe Note

For the interested, natto is boiled and fermented soybeans. Nattokinase is a natural enzyme in natto. Natto gets fermented with Bacillus subtilis. Natto is also available in supplement form. Also, natto is vegan and vegetarian friendly. 

Nutrition Facts of Natto

According to the USDA, 100 g of natto contains:

• Energy: 211 kcal
• Fat: 11 g
• Fibre: 5.4 g
• Sugar: 4.89 g 
• Protein: 19.4 g
• Carbohydrates: 12.7 g
• Sodium : 7 mg
• Calcium: 217 mg
• Iron: 8.6 mg
• Manganese: 1.53 mg
• Vitamin C: 13 mg

Carbohydrates

In natto, there are many forms of carbs. Each has its own set of advantages.

Each cup of natto contains around 6 grams of naturally occurring sugar. Sugar found in foods is less of a worry than sugar taken daily as part of the manufacturing process (called “added sugars”). As a result, sugar gives the body energy to carry out everyday tasks.

Fibre

Fibre is another type of carbohydrate found in natto. When you eat a whole serving of fermented food, you’ll get nearly nine grams. According to the USDA, adults should ingest 28 grams of fibre per day.

Fibre consumption not only aids digestion and regulation and has several other health advantages, such as lowering the risk of cancer, obesity, heart disease, and diabetes. Starch, the leftover carbohydrate in natto, is broken down to give energy to the brain and muscles.

When you eat one cup of natto, the food’s overall Glycemic Load (GI) is nine. Therefore, while calculating a food’s influence on blood sugar, the glycemic load is an indicator that factors in portion size. However, one usually eats natto with rice, which has a higher glycemic index.

For example, according to the University of Sydney, a 150-gram dish of white rice with natto has a glycemic load of 24. On the other hand, meals with a glycemic index of 20 or more are moderate to high glycemic values.

Fats

A one-cup serving of natto contains slightly over 19 g of fat. Polyunsaturated fat makes up the majority of that fat. Polyunsaturated fats can help lessen your risk of heart disease and stroke by lowering low-density lipoprotein (LDL) cholesterol. Natto also contains four grams of monounsaturated fat, another “healthy” fat. Natto contains slightly under three grams of saturated fat.

Protein

Natto is a protein-rich meal. You’ll increase your plant-based protein consumption by 34 grams when you drink a full cup.

Minerals 

Micronutrients abound in natto. A serving of natto contains 2.7mg of manganese, equivalent to 134% of the daily required amount. Manganese is good for enzyme activity and other bodily activities such as blood coagulation and metabolism.

You’ll also get 15 grams of iron (84% of one’s daily needs), 1.2 milligrams of copper (58% of one’s daily needs), 201 milligrams of magnesium (50%), 1,276 milligrams of potassium (36%), 5.3 milligrams of zinc (35%), 305 milligrams of phosphorus (30%), and 15.4 milligrams of selenium (22%).

Vitamins

The vitamins that natto provides can also help you. The meal is rich in vitamin C, delivering over 23 mg, or 38% of the daily requirements. Vitamin C aids in the strengthening of the immune system, the formation of collagen, and iron absorption from plant-based meals. It’s also an enzyme that can aid in the healing of free radical damage. In addition, natto has 0.3 milligrams of thiamin (19% of the everyday need), 0.3 mg of riboflavin (20 per cent of your daily requirement), vitamin B6, folate, & choline.

Natto is one of the most excellent forms of vitamin K sources, especially vitamin K2. Vitamin K is necessary for bone formation and blood clotting prevention. Adult women should have at least 90 micrograms of vitamin K per day, while males should obtain at least 120 micrograms per day, as per the National Institutes of Health. Over 40 mcg of vitamin K is in a one-cup meal.

Health Benefits of Natto

Natto has a wide variety of potential health benefits. Here are among the most important discoveries.

Benefits to the Gastrointestinal System

Bacillus subtilis, a special type of bacterium, is used to ferment natto. This stain and other bacteria strains are being researched for their potential to enhance gut health in people.

This bacterium has probiotic properties. Probiotics are live, beneficial bacteria in the digestive tract that help protect your gut from harmful bacteria, aid digestion, and may have additional health advantages. The total degree of their influence is still under investigation. 

Some studies suggest that eating natto and other fermented dairy products might improve stool frequency, particularly in constipated people. However, more research is needed to understand the advantages better.

Natto Improves Bone Density

Vitamin K2, contained in natto, has shown promise in treating diabetes, cancer, and, in particular, osteoarthritis. Research published in Osteoporosis International studied the effects of natto intake on the bone health of older Japanese men. Researchers discovered that people who ingested more natto had better bone health due to the vitamin K level. However, according to the experts, further study is required to grasp the link. 

Another study looked at the intake of natto by older women. Over the past three years, researchers investigated 944 elder Japanese women for study. Women who ate more natto regularly had higher bone mineral density in certain parts of the body, such as the hip and neck.

Other parts of the body, however, remained unchanged. Surprisingly, the researchers found no advantage in consuming more tofu or soybean products.

Improves Cardiovascular Health

Nattokinase is indeed an enzyme that gets created during the fermentation of natto. It helps to reduce arterial plaque development by acting as a biological blood thinner. In addition, Nattokinase provides cardiovascular advantages, such as lowering the risk of heart disease.

Furthermore, according to various research investigations, the enzyme exhibits antihypertensive, anti-atherosclerotic, sterol, anti-platelet, and neuroprotective properties.

Natto Enhances Longevity

Researchers have connected nattokinase to longevity since it shows a significant reduction in the risk of cardiovascular disease. Heart disease is the world’s most important cause of mortality. 

As per the researchers of 2018 research, natto intake can substantially influence the lifespan of the Japanese people. Furthermore, recent research has found that a high natto intake lowers the risk of overall cardiovascular disease mortality and a lower risk of ischemic heart disease mortality.

Regulates Blood Pressure

Many natto research takes place in Japan, where it is popular. However, one study included 79 people with high blood pressure who lived in North America.

Researchers discovered that nattokinase intake was linked to lower arterial pressure in both women and men. In addition, the results gathered from women indicated a potential decrease in stroke risk.

The HealthifyMe Note

Natto has fewer antinutrients and more probiotics compared to non-fermented soybeans. As a result, it helps your body absorb nutrients well and is excellent for gut health. In addition, natto is high in calcium and vitamin K2, which help build stronger, healthier bones. Natto intake helps prevent premenopausal bone loss due to menaquinone7 and isoflavones. In some cases, natto may help with weight loss, mental health, and cancer prevention.

Potential Side Effects and Allergies Of Consuming Natto

Interference with Medicines

Certain drugs may interact with soy. Several drugs and drug types potentially interfere with soy. Among them are:

• Inhibitors of aromatase
• Substrate medicines for cytochrome P450
• Substrate medicines for P-Glycoprotein
• Uridine 5′-diphosphate-glucuronosyltransferase (UGT) substrate medicines, including tamoxifen.

If you’re unsure if your drug fits into such categories, go to your doctor for further information.

Blood Thinning

Since nattokinase can thin the blood, you should not combine it with other blood thinners like aspirin or warfarin. Individuals with small vessel disease can increase the risk of a brain haemorrhage. People with bleeding disorders like haemophilia and low blood pressure should also avoid nattokinase. 

Women and Children

Concerns are looming concerning soy’s effect on women’s health. Some experts believe that soy eating increases the risk of developing endometrial hyperplasia. However, as per the National Institutes of Health, soy meals do not appear to raise the chance of developing the disease. Furthermore, the government claims that eating soy foods seems safe for women who’ve had cancer or are at risk of developing breast cancer. However, children, pregnant women, or breastfeeding mothers must avoid natto due to a lack of evidence.

Antinutrients

Antinutrients in soybeans are a source of worry for certain people. These are substances that prevent nutrients from being absorbed. Antinutrients can also produce bloating and gas in the gastrointestinal tract. The name “antinutrient” is deceptive because they only have an impact when ingested in significant amounts. Antinutrients in food also get reduced during the fermenting process.

Allergies

The Centres for Disease Prevention and Control have identified eight significant food allergies. One of them would be soy. Dairy, egg, peanuts, tree nuts, grain, fish, or crustacean shellfish are the others. Those who are allergic to soy should avoid natto. Adults may experience itching, hives, eczema, inflammation of lips, mouth, or throat, chest tightness or trouble breathing, wheezing, dizziness, fainting, and, in severe cases, anaphylaxis to the Cleveland Clinic. As per the National Institute for Allergy and Contagious Diseases, children experiencing soy allergies may endure frequent vomiting, diarrhoea, and a failure to acquire weight or height.

The HealthifyMe Note

Natto has side effects on certain people. For example, people with bleeding disorders, who are on blood thinners, people with low blood pressure and on antihypertensive drugs must avoid natto. Also, two weeks before surgery, you must reduce its consumption to ensure no risk of excessive bleeding.

Natto Recipe

You can buy natto from supermarkets or make it at home with this recipe.

Prep: 1 hr

Cook: 24 hrs

Yield: 6 cups

Ingredients 

• Soybean: 2 cup
• Water: 3 tbsp
• Natto starter culture: 1 packet

Instructions

• To prepare the soybeans for fermentation, wash them and soak them in 6 cups of water for 9 to 12 hours (a more extended soaking period is better in colder months).
• Drain the soaking water from the soybeans. Fill a big saucepan halfway with water and cook the beans for 2-3 hours, checking every half hour or so. You want them to be delicate but not mushy so that the spores have enough moisture to ferment, but the finished product is still hard.
• To sterilise a colander, cooking spoon, and casserole dish, rinse or submerge them in hot water.
• Drain the cooked beans in a sterile colander and transfer them to a sterilised casserole dish. Preheat the oven to 100 degrees Fahrenheit by turning on the light.
• 3 tbsp heated and chilled (for sterilising) water, combined with natto powder. Pour the natto spore package over the beans while they are still heated. Then, using the sterilised spoon, gently stir the beans.
• In the casserole dish, spread the beans in a 1-inch layer.
• Cover the casserole dish tightly with aluminium foil. Then, 1″ apart, poke holes in the foil with a pin.
• Allow the natto to ferment for 22 to 24 hours in a covered casserole dish in the oven, dehydrator, or other warmer. Also, keep the temperature constant at 100 degrees F. You know they’ve finished fermenting when you notice a white layer on the beans and smell an ammonia-like odour.
• Allow 2 hours for the Japanese natto to cool at room temperature. For optimum flavour and stringiness, remove the aluminium foil and keep it in sealed containers in the refrigerator overnight.

Conclusion

Natto is a fermented soybean product. Fibre, probiotics, vitamin K2, and nattokinase are all found in natto. This combination may lower cholesterol and blood pressure levels while lowering the risk of heart disease. Natto is particularly healthy since its soybeans undergo fermentation, promoting probiotic bacteria. In comparison to non-fermented soybeans, natto has fewer antinutrients and more probiotics. As a result, it helps your body absorb nutrients more quickly and eliminates unpleasant stomach symptoms. 

Natto is high in calcium and vitamin K2, which help build stronger, healthier bones. In some cases, natto may help with weight loss, mental health, and cancer prevention. More research, however, is required. In addition, people with thinning blood medication or soy allergy should consult a doctor before taking natto.

Frequently Asked Questions (FAQs)

Q. How much natto should I eat daily?

A. There are no general standards for using nattokinase correctly. Even though most producers advise no more than 2,000 FU daily, dosages ranging up to 3,000 FU have already been administered successfully for more than 26 weeks. In contrast to supplements, nattokinase may be obtained by including natto in your diet.

Q. Is natto good for your skin?

A. Natto contains linoleic acid, fibre, and lecithin, which aid digestion and blood purification. Natto is also a source of vitamin PQQ, a dietary vitamin that is necessary for keeping healthy and attractive skin. In addition, blood cleansing is crucial for maintaining good skin. Natto may accomplish both.

Q. Is natto a Superfood?

A. Natto has traditionally been a mainstay of the Japanese diet and can also be referred to as a “superfood” because of its low-calorie and high nutritional content. However, despite its popularity in Japan, natto’s harsh flavour, pungent odour, and sticky texture divide opinion.

Q. Is natto good for gut health?

A. Yes, it is beneficial to your digestive system.

Natto is high in probiotics, which help to improve intestinal health. According to research, having the correct stomach bacteria can aid digestion and treat other problems.

Q. Is it OK to eat natto every day?

A. Most people can consume natto, but those on blood-thinning medications or who have thyroid issues should check their doctor before adding it to their diet.

Q. Is natto anti-ageing?

A. Nattokinase, found in natto, has a high quantity of vitamin K2, an effective natural anti-ageing agent that helps enhance an individual’s general skin health.

Q. Is natto good for hair?

A. Natto is good for your hair and skin. Nattokinase has been linked to metabolism and anti-ageing. Natto Lecithin – Prevents thrombus by keeping the blood thin. It also protects against myocardial and brain infarctions.

Q. Can I eat natto at night?

A. For nattokinase to enter the system efficiently, it must pass through the stomach’s acidic environment in a fair length of time. As a result, the optimal time to consume natto would be on an empty belly.

Q. Does natto increase estrogen?

A. In black soybean natto, the quantity of aglycone daidzein and genistein isoflavones is more significant than in unfermented black soybean. Daidzein isoflavones have a molecular structure that mimics oestrogen, resulting in strong oestrogen activity.

Q. Is natto acidic or alkaline?

A. Natto is an alkaline fermentation, which sets it apart from most other fermentations. Protein is transformed into amino acids in peptide form in alkaline-fermented meals. During the fermentation process, ammonia is generated, which elevates the pH of natto and gives it the unmistakable ammonia scent.

Q. Does natto make you gassy?

A. No. It isn’t the kind of delicate bacteria seen in yoghurt. Natto bacteria are spore-forming bacteria that are resilient. (This is true of all Bacillus bacteria). Freezing does not kill them. Even boiling won’t get rid of them all.

Q. Does natto help you lose weight?

A. Natto is high in probiotics and fibre, which may help prevent weight gain and optimise weight reduction.

Q. Does natto lower cholesterol?

A. You can lower cholesterol with natto. This fibrinolytic enzyme is particularly efficient in dissolving thrombus (clots) through blood in human and animal experiments.

Q. Is natto a prebiotic?

A. Natto is a fantastic prebiotic, but it’s even better because it’s rich in vitamin K2. Part of the reason you’re unfamiliar with vitamin K2 is that it’s not available in many foods. So the best source is undoubtedly natto.