My first encounter with natto was inauspicious.
One night in July 1998, I was on assignment in Tokyo for This Old House magazine.
It had been a long, odd day.
I was there to gather “good ideas” from the Japanese housing industry. I was supposed to write about its electric composting machines, high-tech toilets (which diagnosed illness by analyzing the user’s “sample”), and other snappy Asian fin-de-millennium domestic innovations.
That afternoon, the CEO of one of the biggest homebuilders in Japan had told me, “After World War II, America had bombed most of Tokyo flat. That created lots of room to build new houses. So we thank you Americans for helping this company get started!”
After five seconds of silence, all I could muster was: “Uh… you’re welcome?”
The 30 other execs in the room roared with laughter.
Twenty minutes later, disoriented by this exchange, I wandered into the Shibuya nightclub district with my translator.
Back in 1998, American magazines still had money. So they allowed writers to file the tab for lubricated evenings loosely under “background interviews.”
My translator and I were not interviewing anyone except each other, but hey, this article needed some local color, and I clearly didn’t understand Japanese culture yet.
(Note: I still don’t.)
So in a bar the size of a Chevy van, after an untoward quantity of sake drunk from little wooden boxes, he placed a plate of grayish-brown beans in front of me.
That night, I’d already eaten little dried eels — complete with little dried eel eyes staring plaintively — so beans seemed like all-American comfort food by comparison.
Yet they glistened… oddly…
As I raised them to my lips, spider-webbish white threads trailed off from my chopsticks.
What is this stuff?
The dish was natto, a Japanese delicacy made of soybeans fermented with Bacillus subtilis var. natto.
Americans have called the taste of natto “disgusting” and worse — a common Internet comment is that it tastes like an unholy alliance between stinky cheese and unwashed gym socks.
I won’t go that far, but I will say there’s nothing in the flavor of natto to immediately make one a diehard fan. To me, it tasted slimy, smoky, and bitter.
But years later — this year, in fact — I started digging into the health benefits of vitamin K2. This nutrient is one of the least known yet most vital for heart, bone, and brain health.
As it turns out, K2 tells calcium where to go in the body.
Here’s the story: In 2004, UCLA researchers discovered that stiffened atherosclerotic arteries contained a special protein — one previously believed to exist only in bones.1
This protein helps bones grow — so what was it doing inside arteries? The researchers realized that a lack of vitamin K2 prevented free calcium in the blood from going where it should — to the bones and teeth.
Instead, it wound up inside the arteries, rendering them stiff and subject to clots and rupture.
The solution? Eat more K2! It directs calcium to the skeleton, keeping it strong, and away from the heart and blood vessels, keeping them calcium-free and supple.
And what’s the best food source of K2? Cheese, egg yolks, and butter aren’t bad, but the K2 winner is…
You guessed it — natto!
For $1.99, my local Asian grocer sells four 46-gram packets of frozen natto, each in a polystyrene container. One of these yields about 600 micrograms of natto — roughly three times the dose found in research to improve cardiovascular and bone health.
So now the great natto experiment is on. I eat natto virtually every morning. It’s essentially my breakfast “dessert.”
But I understand that others may never be able to accept its odd flavor (my wife, a typically adventurous eater, says it’s the one food that invariably triggers her gag reflex).
So if natto is not your thing, another terrific way to get it is via a vitamin D3/K2 supplement. However, be very careful. You must make sure the supplement provides K2 in something called the MK-7 form, which gives it a long, effective life in the body. It should also be GMO-free.
Most of all, don’t think that just any version of vitamin K is what you need. Vitamin K1, for example, comes from leafy greens and is typically easy to get from the diet. Vitamin K1 can convert to K2 in the body, but this is often inefficient. For maximum benefit, take vitamin K2.
This is, understandably, a tall order. But don’t worry. Living Well is on the case, and we’ll be offering you a solution very soon.
Editor, Natural Health Solutions
 Abedin M, Tintut Y, Demer LL. Vascular calcification: mechanisms and clinical ramifications. Arterioscler Thromb Vasc Biol. 2004 Jul;24(7):1161-70.