Natto: Another fermented food I probably should be eating

http://www.jafra.gr.jp/eng/sumi.html

Natto
How appetizing is this? Creative Commons License photo credit: jasja dekker

Prior to Seth Roberts mentioning it on his blog (here), I had never heard of the Japanese dish called “Natto,” which is a fermented soybean product. Apparently, it contains a great deal of Vitamin K2, is anti-bad-bacterial, and effectively lyses human thrombus. If you’re like me, that last bit probably made no sense to you, so below are some definitions until I paste liberally from an interview on Natto held with a Japanese expert on the food, Professor Hiroyuki Sumi, who has been nicknamed “Dr. Natto.”

  • Nattō – “A high protein food consisting of sticky, fermented whole soybeans cooked in Bacillus natto.”
  • lyse – “To dissolve or destroy.”
  • thrombus – “A clot within the cardiovascular system. It may occlude (block) the vessel or may be attached to the wall of the vessel without blocking the blood flow.”
  • fibrinolytic – “Fibrinolysis is the process wherein a fibrin clot, the product of coagulation, is broken down.”

The K2 angle on Natto is particularly fascinating, particularly in light of how expensive it is to supplement K2 via products like butter oil. I’ve been wondering in reading more into fermentation from sources like Seth Roberts when I would see a tie-in to Vitamin K2, which is produced by our own gut bacteria as noted below.

In an experiment conducted out of sheer curiosity, I found that natto contained a strong enzyme that lyses thrombus.

I am Japanese and regularly eat natto, so one day I took some natto to my laboratory. That was in 1980. I usually prepared thrombus in a laboratory dish and measured its strength by adding urokinase to it, but that day, I added natto instead. I found that natto contained a strong fibrinolytic enzyme, judging from the large area lysed. After coming back to Japan, I repeated various experiments, and first presented the results of my research in 1986. NHK and various newspapers reported my discovery of the enzyme named ’nattokinase ’,and before I knew it, I had become Dr. Natto. Originally, I was interested in fermentation. After I graduated from the Department of Fermentation Technology at Yamanashi University, I entered the Department of Medicine because I wanted to continue my study of enzymes further. In the field of fermentation, Japanese technology is the most advanced in the world. I think this is the field in which we achieve our most original results.

I studied more than 200 foods from all over the world, but none surpassed natto in terms of fibrinolytic activity.

――What are the functions of nattokinase and Vitamin K2, which are contained in natto?

Dr. Sumi: It is said that natto became a popular food in the Edo period, and that the voice of natto sellers was constantly heard in the city of Edo.Regarding the effects of natto,there are many anecdotes concerning its efficacy for stomachache, and flu, and for helping women give a birth. This is because natto has a high nutritive value and is easy for the body to absorb. In addition, natto has an antibacterial effect. In the old days, food poisoning was very common, and people used natto in order to prevent cholera, typhoid and dysentery.

Natto is highly antibacterial, and also contains di-picolinic acid, which suppresses O-157.

In a food dictionary of the Edo period, it is written that natto neutralizes poisons and stimulates the appetite.Neutralize poisons refers to an antibacterial effect. Recently, it has been found that natto contains di-picolinic acid, which suppresses O-157, and that natto has an antibiotic effect. Natto suppresses the growth of harmful bacteria while encouraging the growth of beneficial bacteria such as lactobacillus. The best-known component of natto is nattokinase, an enzyme that lyses thrombus. Recently, the Japanese diet has come to resemble the American one, and consequently, the incidence of thrombosis in Japan has increased. The incidence of thrombosis in the heart and brain is higher than that of cancer, if myocardial infarction and cerebral infarction are included in the total. Natto has attracted attention as a food that helps to prevent senile dementia, which is one type of thrombosis, because nattokinase lyses thrombus for a very long time when eaten directly instead of taken by injection.

Vitamin K2 in natto is essential for preventing osteoporosis.

Natto contains another useful component, named Vitamin K2. It is said that 60% of women over the age of 60 suffer from osteoporosis, which Vitamin K2 helps to prevent. In order to maintain healthy bones, a number of studies suggest that it is important to obtain Calcium and Vitamin D from milk. Recently, however, it was found that a protein named osteocalcin acts as a kind of glue that helps to incorporate Calcium into the bones, and that Vitamin K2 is necessary in order to produce this protein. Furthermore, according to the results of recent epidemiological research, the amount of Vitamin K2 in the body of people who suffer from osteoporosis is decreasing compared with that of healthy people.

Obtaining sufficient Vitamin K2 is not a problem for healthy people, because they have a colon bacillus that is constantly producing Vitamin K2 in the alimentary canal. However, when people become older, or take medicine containing antibiotics, this bacillus weakens and produces less Vitamin K2. It is becoming clear that Vitamin K2 produced by this bacterium is closely connected with the prevention of osteoporosis, and the Ministry of Health and Welfare has approved Vitamin K2 as a medicine for osteoporosis. Unlike natto, yeast, a lactobacillus, and Koji do not contain Vitamin K2 that comes from a bacterium. Bacillus natto is a unique bacterium throughout the world, and moreover people can ingest it in the raw. Therefore, natto is receiving considerable attention as the only food that contains Vitamin K2 from a bacterium.

Vitamin K2 has the chemical name menaquinone 7. At present, Vitamin K1, or menaquinone 4, is synthesized for use in the medicines approved by the Ministry of Health and Welfare. When the components of blood are analyzed, one vitamin that is found more often in healthy people than in osteoporotic people is menaquinone 7. A lack of menaquinone 7 causes osteoporosis. Because Bacillus natto produces menaquinone 7, eating natto helps to prevent osteoporosis. It is important to obtain the fundamental components of bones by consuming milk and Shiitake mushrooms, but Vitamin K2 is also necessary. Menaquinone 7 has only recently appeared in the analysis data of the Science and Technology agency, and samples are not on sale yet.

It is possible to obtain enough vitamin K2 from one packet (100 g) of natto.

One hundred grams of natto contains approximately 1,000μg of menaquinone 7. A normal person is supposed to consume 1μg per 1 kg of body weight each day, which means that a person of 60 kg should consume 60μg of menaquinone 7. Therefore, 10 g of natto supplies enough menaquinone for one day. If the colon bacillus is weakened, a packet of natto supplies a sufficient amount of menaquinone 7.

As a result of attempts to make natto more palatable, the amount of its effective components decreased.

Extremely undeveloped natto has been increasing as a result of attempts to make natto more palatable, especially for people in the Kansai area in Japan. Such natto has a weaker odor and is less sticky. When the US authorities occupied Japan in 1945, they prohibited the sale of natto because they thought that cholera and typhoid were often caused by such a rotten food. Since then, about three types of purely cultured bacillus have been used to make natto. As a result, natto became tastier and safer, but on the other hand, the amount of the anti-bacterial material, Vitamin K2, and nattokinase decreased. Comparing a 1936 report on the components of natto and its activity with current data, it is found that the anti-bacterial component has dramatically decreased.

Kombucha Tea (Fermented Food)

http://www.blog.sethrober…#comment-275794

More from Seth Roberts in the self-experimentation with fermented foods (And satisfaction of umami/flavor cravings) comes discussion of using Kombucha Tea (a fermented tea) to test effects on overall health.

I’ve never had Kombucha tea, but apparently you can make it at home.

Anyone know how? As homemade fermented foods go, this sounds much more appealing to me than homemade yogurt.

4. My idea that we like umami tastes, sour tastes, and complex flavors so that we will eat more bacteria-laden food (which nowadays would be fermented food) is saying that we need plenty of these foods. Why else would evolution have tried so hard to make us eat them? The implication is they should be part of every diet, like Vitamin C. When someone deficient in any vitamin begins eating that vitamin, the deficiency symptoms go away very quickly, within a few weeks, usually. The changes are easy to notice. So the details of what Tucker observed – the speed and size of the improvements — support my general idea that there is a widespread deficiency here that can be easily fixed.

How to Eat Grains

http://wholehealthsource….eat-grains.html

Continuing the recent interest in fermentation (See discussion of Seth Roberts’ posts on Probiotics and Your Immune System and The Staggering Greatness of Homemade Yogurt) comes this post from Stephan at Whole Health Source discussing how to eat grains.

There are two ideas that seem to be repeatedly coming to the surface here:

  • Carbohydrates seem to be better for human consumption when fermented as fermentation reduces anti-nutrients and even introduces some new nutrition in the process.
  • Foods that don’t seem “paleo” at first blush maybe just need some fermentation, which is really just another way of saying they need to be pre-digested prior to eating.

Regarding that second point, our hunter/gatherer ancestors had little food storage tech. This has two implications in my mind:

  • Food is consumed fresh if at all possible, to the point of gorging. Our bodies have an amazing ability to store excess carbohydrate consumption efficiently as fat.
  • Food found but not readily consumed rots or ferments. Our bodies do well with this (Evolutionary luck or design?) by receiving immune system boosts from the introduction of bacteria, reducing toxins via fermentation and maximizing nutrient absorption.

Anyway, here is Stephan:

The second factor that’s often overlooked is food preparation techniques. These tribes did not eat their grains and legumes haphazardly! This is a factor that was overlooked by Dr. Price himself, but has been emphasized by Sally Fallon. Healthy grain-based African cultures typically soaked, ground and fermented their grains before cooking, creating a sour porridge that’s nutritionally superior to unfermented grains. The bran was removed from corn and millet during processing, if possible. Legumes were always soaked prior to cooking.

These traditional food processing techniques have a very important effect on grains and legumes that brings them closer in line with the “paleolithic” foods our bodies are designed to digest. They reduce or eliminate toxins such as lectins and tannins, greatly reduce anti-nutrients such as phytic acid and protease inhibitors, and improve vitamin content and amino acid profile. Fermentation is particularly effective in this regard. One has to wonder how long it took the first agriculturalists to discover fermentation, and whether poor food preparation techniques or the exclusion of animal foods could account for their poor health.

Probiotics and Your Immune System

http://www.blog.sethrober…-immune-system/

More from Seth Roberts on fermentation and bacteria, specifically with regards to probiotics:

My take is that our immune systems need a steady stream of foreign pathogens (e.g., bacteria) and pieces of pathogens (e.g., bacterial cell walls) to stay “awake”;. When your immune system is working properly you fight off all sorts of bacteria and viruses without noticing. When your immune system isn’t working properly it overreacts (allergies) and takes too long to react (infectious diseases). Weston Price found twelve communities eating traditional diets whose health was excellent. Their diets varied tremendously but one thing they had in common was daily consumption of fermented foods, including cheese, kefir, sauerkraut, and fermented fish. This supports Amy’s story right down to the dosage. If you don’t eat fermented foods, you might use hookworms, which excrete a steady stream of foreign substances into the blood. (Thanks, Tom.) Hookworms definitely reduce allergy symptoms; I don’t think anyone has asked if they reduce colds and other infections.

The hygiene hypothesis.

The Staggering Greatness of Homemade Yogurt

http://www.blog.sethrober…omemade-yogurt/

I’m not sure why I waited so long to subscribe to Seth Roberts, self-experimenter extraordinaire and creator of the Shangri-La Diet, but after seeing enough shared items of his (H/T Patri Friedman), I finally did. And so far, I’m thoroughly enjoying his typical thought-provoking blog posts.

Recently, he’s been discussing how ice chewing is a sign of iron deficiency. Why is there a relationship here? Ice crushing is similar to bone-crushing, and bone marrow is high in iron. In other words, we are evolutionarily programmed to want to chew bones when we are iron deficient. More from Seth on that topic.

Of course, chewing ice provides us with no iron! That’s a problem.

Similarly, we may have desire for certain tastes out of a need for a certain type of nutrition. Seth has been wondering if the desire for taste is really a manifestation of a need for bacteria, as fermented foods tend to be very nutritious thanks to the bacteria and the neutralization of the bad stuff in the foods fermented (I.e. fermented soy reduces the toxin phytate. Dairy fermentation reduces lactose content.).

So where does that leave Seth? Super-fermented (read: sour!), sour yogurt of course!

I’m not ready to try this one out as it sounds kinda gross and I’m just not into yogurt at this point. The non-photogenic comment by Seth at the end makes it not so appealing, too.

However, I’m saving this down for posterity:

I had made yogurt dozens of times. This time, however, I wanted to get as much bacteria as possible so I incubated it about 24 hours instead of about 6 hours. It came out far more sour (due to lactic acid) than ever before. But it wasn’t just really sour (like vinegar); it also had complexity of flavor, creaminess, and a pleasant consistency. It was more sour (tart and tangy are the conventional terms) than any yogurt I’ve ever had. I couldn’t eat a bowl of it; I had to eat it with other food. This may be why commercial yogurt is mild: So you will/can eat more of it at one time.

The yogurt I made is essentially a condiment, although it can be mixed with fruit. It improves almost anything: soup, meat, fish, fruit, string beans, scrambled eggs. (Because almost nothing we eat is sour and almost nothing we eat is creamy.) It is better than other common condiments, such as mustard and chutney, because of its creaminess. It is also far cheaper than other condiments. A small bottle of mustard might cost $3. The same volume of homemade yogurt would cost about 10 cents. (You might need twice or three times as much yogurt to get the same effect.) It is far easier to make than other condiments. And, above all, I suspect it is infinitely better for your health. Mustard has few bacteria. If you complexify and sour your food with mustard, you are essentially chewing ice.

Recipe. I took a gallon of whole milk, mixed it with 2 cups of powdered milk, heated it at about 200 degrees F. for 10-20 minutes (I’m unsure if this step is necessary), cooled it down to 130 degrees F., added 1/2 cup of starter (from other yogurt), and then incubated it in my oven at about 110 degrees F. for about a day. I divided the mixture into four glass containers. Although the lowest possible setting on the oven is “WARM”, which was too hot, the thermostat actually works at lower temperatures. I set it below WARM and used a room thermometer to adjust the setting so that the temperature was about 110 degrees. (The photo above is not mine, incidentally. My yogurt is no longer photogenic.)