The origin of natto can be traced back to the Jomon and Yayoi periods in Japan, and it is a traditional Japanese food. For Japan, which mainly consumes rice as its staple food, natto is an indispensable dish on the table. To date, the topic of "the deliciousness of natto and its maintenance" can be seen in various books and magazines. However, articles about "the efficacy of natto" are extremely common.
Recently, with Japan becoming the world's longest-lived country, research on Japanese diet has become very popular. As a result, "soybean processed foods," one of the major characteristics of Japanese diet, has become a focus of attention. Among the processed soybean products such as miso, soy sauce, and tofu, natto stands out as an extraordinary existence generated from soybeans and bacteria. With the increasing scientific evaluation of natto, its various astonishing effects have been proven one by one. For example, natto has the functions of anti-cancer, antibacterial, anti-aging, prevention and treatment of adult diseases, etc. Natto, which has always existed in our lives without attracting much attention, actually possesses surprising effects. Here, we want to reveal the true nature of natto and make a contribution to the improvement of dietary life and health promotion.
The content introduced in this book is a partial summary of recent research on natto, hoping that more people will read and understand the benefits of natto.
Chapter 1: The History of Natto
1. The Deliciousness of Natto Known to Jomon People
When did the Japanese start eating natto?
This is still an unsolved historical mystery, but there is a legend among the people. During the late Jomon period, when the cultivation method of rice was introduced from China, there was already a food similar to natto.
Although at that time there was no name for what we commonly eat as "natto," there is indeed a possibility that the Jomon people consumed a kind of bean that was sticky, stringy, and could pull out long threads.
The Jomon period lasted approximately 10,000 years, from 12,000 years ago to 2,300 years ago. At that time, the main foods were chestnuts, walnuts, acorns, millet, foxtail millet, sweet potatoes, yams, and taro. Other foods included fish, wild vegetables, and wild mushrooms. About 80% of their daily food came from animal sources.
Similar to the paste made from mashed sweet potatoes, the viscous substance of natto made from fermented soybeans was where its deliciousness lay. For the Jomon people who were accustomed to raw sweet potato juice, the stringy beans were not surprising.
Like tracing the history of rice, soybeans were also introduced from the Chinese mainland to Japan during the late Jomon period. Japanese-grown rice plants have about 10 million spores attached per plant. When bundled together, they form a container-like shape called "hull." Placing cooked soybeans inside would produce sticky, stringy natto.
What is now considered a specialized container for natto was, in ancient times, a versatile container used in daily life. The scientific name for natto bacteria is Bacillus subtilis natto, a type of bacillus. This bacterium exists not only in grasses but also in soil, straw, and air.
Since the Jomon people lived in fixed nests, which in a sense served as fermentation chambers, and because they used straw as bedding in their daily lives, the appearance of natto was not without reason.
2. Soybeans Were Once Universal Medicines
It is not feasible to maintain health solely through medication in daily life. The most important thing is having three meals a day: breakfast, lunch, and dinner.
The longest-lived people in the world are the Japanese. However, even the longest-lived individuals would lose the joy and dignity of living if they became afflicted with dementia or spent their days bedridden. There are probably few people who simply wish to live longer without considering the quality of life.
Therefore, diet is more important than anything else. For the Japanese, soybeans are a comprehensive nutritional food rich in calcium and vitamins, possessing magical power in maintaining a healthy physique.
From the records in the ancient Japanese medical book "Ishinhon," we can see the following:
* Steaming or boiling soybeans has greater efficacy than rice.
Eating boiled soybeans initially may make you feel heavy, but after a year of continuous consumption, you will feel light and experience improved sexual function.
* Roasted soybean powder has a sweet taste, improving gastrointestinal function and alleviating swelling and numbness.
Soaking roasted soybeans in alcohol can be used for health preservation.
Eating boiled soybeans along with the broth can detoxify the body.
* Soybeans can prevent and treat constipation.
During the Nara period, there were records in government offices of distributing soybeans as medicine to monks suffering from beriberi, providing each person with one liter.
The phrase "foot disease arises, making daily life inconvenient" clearly refers to beriberi. Soybeans contain vitamin E, other vitamins, minerals, isoflavones, saponins, and various components effective in restoring physical strength.
3. Making Soybeans into Natto Doubles Its Functionality
Natto not only contains all the high-quality components found in soybeans but also includes new components generated through the fermentation process.
Vitamin B2 is one of them. In 100g of soybeans, there is 0.3mg of vitamin B2, whereas in natto, there is 0.56mg. This increased component is produced by the action of natto bacteria, and different types of natto can contain up to 3-4 times more vitamin B2 than soybeans.
Vitamin B2 enables the smooth burning of fats accumulated in the body, playing a role in beautifying the skin and preventing obesity. It is an essential component for weight loss.
The fat-decomposing function of vitamin B2 is also effective in preventing arteriosclerosis and diabetes. Vitamin B2 also promotes the growth of children and is crucial for those in their growing phase. The preference of many children for natto can be attributed to their body's needs.
Additionally, vitamin B2 alleviates fatigue, enhances liver function, and breaks down alcohol. Therefore, consuming natto as a side dish with alcohol can serve as a hangover remedy.
In another chapter, it is explained that vitamin K2 improves bone health in middle-aged and elderly women, and natto is rich in vitamin K2. Since soybeans do not contain vitamin K2, it is produced due to the fermentation by natto bacteria.
The stringiness of natto significantly impacts its flavor. The main component of the strings is glutamic acid, which is also produced by the action of natto bacteria. The stringy components protect the inner lining of the stomach and facilitate the excretion of food and waste in the intestines. Nattokinase, which dissolves blood clots in blood vessels and has garnered significant attention, is also produced due to the action of natto bacteria.
4. Breakfast Food That Boosted the Intellectual Capacity of Tokyo Residents - Natto
In Japanese history, aside from the present era, natto was also highly popular during the Edo period. In books from that time, there is a saying: "There may be days when crows don't caw, but there are no days when natto isn't sold. This is because natto is a local favorite."
As dawn approaches, the cries of natto vendors and peddlers can be heard. Initially, natto was a winter food, but by the mid to late Edo period, in large cities like Tokyo, natto had become an indispensable commodity throughout the year.
In the historical texts of that era, the production process of natto is described as follows:
"Cook soybeans, leave them indoors overnight, and then sell them. In winter, cold regions often experience vegetable shortages, so natto is used as a supplement. Even in Tokyo, natto is sold in summer. It can be eaten as soup or with soy sauce. In Kyoto, most natto is self-produced, so it is not easily found in stores."
During the Edo period, the region north of Tokyo was the area with the highest consumption of natto in Japan. Natto contains large amounts of components that enhance creativity, intellect, and foresight, such as lecithin, glutamic acid, and vitamin B. These components played a certain role in the subsequent development of Tokyo into a world-renowned metropolis.
5. People from Kansai Were Also Surprised by the Good Taste of Natto
Yasu Eguchi (Naval Surgeon Commander), who served as the Chief Medical Officer of the Japanese Navy during World War II, can be regarded as a pioneer in natto research. In 1942, he wrote the book "The Urgent Task of Popularizing Natto Today," emphasizing the advantages of natto as a food. The main points were as follows:
1) As a side dish to rice, fish and meat require additional supplementation of fats. However, soybeans can fully meet the needs for protein and fat. Eating natto is akin to simultaneously consuming rice, fish, and meat.
2) Natto bacteria have bactericidal effects on various pathogens, especially dysentery and malaria. To prevent these diseases, natto should be utilized effectively.
3) Consuming small amounts of natto, with its unique flavor and probiotic effects, can stimulate appetite and aid digestion.
4) Natto is an excellent food that should not only be promoted in Japan but also in other countries.
At that time, natto was still a regional food in the Kanto and Tohoku areas, not only having a unique flavor, but during the war, due to the rationing system, many people began to know the delicious taste of natto. After the end of World War II, with the return of demobilized soldiers, natto spread nationwide, greatly promoting its popularity.
People from Kansai, Shikoku, Kyushu, and Okinawa initially disliked natto, but as they became familiar with and adapted to it, they developed a stronger liking for it than people from the Tohoku region. From the perspective of the current nationwide natto craze, this is truly unbelievable.
6. The Person Who Saved Natto After the War
On August 15, 1945, after a prolonged and arduous war, World War II finally ended with Japan's surrender.
After the war, an unprecedented food shortage occurred. On November 1, 1945, the National Starvation Countermeasure Citizens' Conference was held. At that time, starvation deaths were occurring frequently across Japan, particularly in large cities.
In the black markets around the country, people resorted to bartering goods, carrying precious metals to purchase food from all over Japan just to fill their stomachs. Many tragic incidents happened during this period.
At that time, in the headquarters of the American Occupation Forces in Japan, there was a person deeply moved by the dire nutritional state of the Japanese people—Hao, the nutrition director of the occupation forces. He was very dissatisfied with the revitalization plan formulated by the Japanese Ministry of Agriculture, Forestry, and Fisheries. After studying Japanese dietary culture, he took notice of natto and collected a lot of information from natto researchers and producers. As a result, he concluded that "the most economical and effective way to meet the necessary nutritional requirements of the Japanese people is natto."
Despite his high position, in August 1947, he personally went to Sendai and met with Professor Kondo of the Department of Medicine at Tohoku University, asking detailed questions about natto.
With his emphasis, the Japanese government also began to pay attention to natto, and thus a new chapter in the post-war history of natto was unveiled.
7. The Japanese Should Eat More Natto
Amidst the chaos after the war, to make the headquarters of the occupation forces understand natto, the Natto Producers Association commissioned the writing of the book "Natto (Soy Cheese)." The book provided a detailed introduction to the origins of natto, its popularization status, modern production technology, and hygiene. To better convey the message to foreigners, it was named "Soy Cheese" and introduced the nutritional effects and specific data of natto.
In 1949, at the main store of Mitsukoshi Department Store, the Soy Culture Expo was held. The chief officer of the occupation forces attended the scene and showed great interest in the book. Afterwards, she also visited a natto production factory.
It was at that time that they reached the conclusion on how to address the protein deficiency among the Japanese after the war: "The Japanese should eat more natto to compensate for the lack of protein."
In western Japan, the consumption of natto has also been continuously increasing.
The historically long-standing natto continues to expand its consumption in modern society. In 1997, the amount of soybeans used to produce natto was 110,000 tons. Converted to 50g per box of natto, it equates to 4.4 billion boxes. That is to say, including the elderly and children, the average Japanese person consumes 35 boxes of natto.
In 1999, the average household in Japan spent 4097 yen on natto, equivalent to 250 RMB. On average, consumption is still higher in the eastern regions, but in western Japan, the consumption of natto is also rapidly expanding.