What Is Natto? Exploring the Fermented Superfood of Japan

Japan is a country celebrated for its vibrant culture and rich culinary traditions, many of which are built on foods that offer incredible health benefits. Among these treasures is natto, a fermented soybean dish with a history that spans centuries. Known for its sticky texture, pungent aroma, and distinctive flavour, natto might not win everyone over at first bite, but its health benefits make it a standout in the world of superfoods.

In this blog, we will explore everything you need to know about natto: what it is, how it is made, its deep roots in Japanese history, and the remarkable benefits it offers for health. Whether you’re curious to try natto for the first time or want to learn why it is considered a nutritional powerhouse, this guide will give you all the answers.

What Is Natto?

Natto is a traditional Japanese food made by fermenting soybeans with a bacterium called Bacillus subtilis. This fermentation process gives natto its unique characteristics: a sticky, stringy texture, a strong aroma, and a nutty, earthy flavour.

While natto may seem like an acquired taste to some, it is a beloved staple in Japanese households, particularly at breakfast. It is most commonly served over steamed rice, often with soy sauce, mustard, or other seasonings. Beyond its culinary appeal, natto has earned a reputation as a superfood because of its extraordinary nutritional content and potential health benefits.

The History of Natto

The origins of natto are as fascinating as the dish itself. Natto is believed to have been discovered over 1,000 years ago, likely by accident. Legend has it that soybeans stored in straw—a natural source of Bacillus subtilis—fermented over time, creating the sticky, fermented beans we know today.

Historically, natto was especially popular in northeastern Japan, where it provided an essential source of nutrition during the harsh winters. Its ability to energise and sustain made it a vital food for farmers and workers. Over the centuries, natto evolved from a regional speciality to a nationwide staple. Today, its popularity has spread beyond Japan as more people around the world discover its unique taste and health-promoting properties.

How Is Natto Made?

The process of making natto is a carefully crafted blend of science and tradition. While it might seem simple, each step is essential to achieving natto’s distinct texture, flavour, and nutritional value.

1. Preparing the Soybeans

The journey begins with selecting high-quality soybeans. These are soaked in water to soften them, then steamed until fully cooked. The soft texture of the soybeans is crucial for fermentation.

2. Adding the Bacteria

Once the soybeans are prepared, they are inoculated with Bacillus subtilis, a bacterium that drives the fermentation process. This step is where the magic happens, as the bacteria begin to transform the beans.

3. Fermentation

The inoculated soybeans are kept at a warm temperature—around 40°C (104°F)—for 24 to 48 hours. During this time, the bacteria create the sticky, stringy texture and develop natto’s signature aroma and flavour.

4. Aging

After fermentation, the natto is chilled and aged for several days. This allows the flavours to mature and reduces the intensity of its smell, making it more palatable.

The result is a dish that is rich in probiotics, enzymes, and nutrients—a true superfood.

Nutritional Benefits of Natto

Natto is often celebrated as one of the most nutritious foods on the planet. A single serving offers a wealth of vitamins, minerals, and beneficial compounds that support overall health.

• Rich in Protein

Natto is a complete plant-based protein, containing all nine essential amino acids. This makes it an excellent choice for vegetarians and vegans.

• High in Vitamin K2

One of natto’s standout features is its high vitamin K2 content, which is essential for bone health and cardiovascular health.

• Packed with Probiotics

The fermentation process fills natto with beneficial bacteria that support gut health.

• Contains Fibre

Natto’s fibre content aids digestion and helps maintain a healthy gut microbiome.

• Loaded with Minerals

It provides essential minerals like calcium, magnesium, and iron, which are crucial for overall health.

• Rich in Nattokinase

This enzyme, unique to natto, is known for its cardiovascular benefits, including its ability to break down blood clots.

The Health Benefits of Natto

1. Stronger Bones

Natto’s high levels of vitamin K2 play a key role in bone health. This nutrient helps direct calcium to the bones, strengthening them and reducing the risk of fractures. Regular consumption of natto may lower the risk of osteoporosis, particularly in older adults.

2. Improved Heart Health

The enzyme nattokinase has been extensively studied for its ability to break down fibrin, a protein that can cause blood clots. By improving circulation and reducing clotting, natto supports cardiovascular health and reduces the risk of heart attacks and strokes.

3. Enhanced Digestive Health

The probiotics in natto help balance the gut microbiome, supporting digestion and nutrient absorption. A healthy gut is linked to improved immunity and reduced inflammation throughout the body.

4. Boosted Immune System

Natto’s combination of probiotics, fibre, and antioxidants helps strengthen the immune system, making it easier for the body to fight infections and illnesses.

5. Youthful Skin

The antioxidants in natto help combat oxidative stress, which can contribute to premature ageing. Vitamin E and other nutrients in natto support healthy, radiant skin by improving elasticity and reducing wrinkles.

6. Weight Management

Low in calories but high in protein and fibre, natto is a filling food that helps regulate appetite and supports healthy weight management.

How to Enjoy Natto

If you’re new to natto, its strong smell and sticky texture might seem daunting. However, with a little creativity, you can learn to enjoy this superfood and reap its many benefits.

• Classic Natto Bowl

The traditional way to eat natto is with steamed rice. Simply mix the natto well (stirring enhances its flavour), then add soy sauce, mustard, or spring onions for a delicious meal.

• Natto Salad

Combine natto with fresh vegetables, a drizzle of sesame oil, and a sprinkle of sesame seeds for a nutrient-packed salad.

• Natto Sushi Rolls

Wrap natto in seaweed with rice and vegetables for a healthy twist on sushi.

• Natto Toast

Spread natto on whole-grain toast and top with avocado or a poached egg for a hearty breakfast.

• Smoothie Boost

For the adventurous, blend natto into a smoothie with fruits and vegetables for a unique nutrient boost.

Tips for First-Time Natto Eaters

• Start Small: Begin with a small portion to get used to its flavour.

• Mix Well: Stirring natto thoroughly enhances its taste and texture.

• Pair with Familiar Flavours: Natto's strong taste can be balanced by pairing it with mild or familiar foods like rice or bread.

Where to Find Natto

Natto is widely available in Japanese supermarkets and Asian grocery stores, often sold in small pre-packaged portions. Many online retailers now offer natto for those outside Japan, making it accessible worldwide.

Is Natto Right for Everyone?

While natto is a superfood, it isn’t suitable for everyone. Due to its high vitamin K2 content, people on blood-thinning medications should consult their doctor before consuming it. Additionally, those with soy allergies should avoid it altogether.

The Verdict on Natto

Natto is more than just a traditional Japanese dish; it’s a superfood with a rich history and incredible health benefits. From improving bone and heart health to supporting digestion and boosting immunity, natto has become a staple of healthy eating.

Although its flavour and texture may take some getting used to, the benefits of incorporating natto into your diet are well worth the effort. Whether enjoyed the traditional way or as part of creative recipes, natto offers a unique combination of taste, history, and nutrition.

So, what is natto? It’s a centuries-old gem of Japanese cuisine that continues to amaze with its versatility and health-promoting properties. Why not try this fermented treasure and discover its benefits for yourself?