In recent years I’ve experimented with different ways of eating – vegetarian/vegan, gluten-free, paleo. And while the gluten-free thing I’m going to try to stick with, what is increasingly making the most sense is to have a diet that is widely inclusive. There’s a hypothesis called the triage theory of aging, which reasons that when the body is facing micronutrient deficiencies, it will sacrifice processes that support longevity in order to prevent acute deficiency symptoms. If these deficiencies are short-term, this is likely not problematic. But if you’re chronically deficient in a micronutrient, this theory posits that your body will consistently shut down processes that contribute to long-term health in order to carry out those that are necessary to keep you alive day-to-day. Few people these days suffer from acute vitamin D deficiency (i.e. rickets), but it could be that many people don’t have levels that are optimal for long-term disease protection.
Eating a wide variety of natural unprocessed foods seems to be the way to go. Luckily I’m quite fond of food, plants and animals both. It’s rare that I encounter something that I hear is very healthful that is also distasteful. But one such food is natto.
I learned about natto from the book “Vitamin K2 and the Calcium Paradox” by Kate Rheaume B. It’s a well-written book, not heavy on the science but not so simplistic that it feels condescending, like some science-for-the-nonscientist books can be. I’d heard about K2 prior to reading this book mostly from internet-readings related to the Weston A. Price foundation. During his world-wide adventures chronicling the health of various aboriginal peoples, he discovered a correlation between a nutrient he termed the “X factor”, and the healthy, normal development of bones, teeth and facial structures. This X factor was found in things like egg yolks and grass-fed butter.
Later it became clear that the X factor was in fact Vitamin K2, a little-known vitamin overshadowed by it’s more famous sibling, Vitamin K1. The greater awareness of K1 is due to the salience of its deficiency syndromes – K1 is vital for proper blood clotting, and if you’re acutely deficient, you’ll know it. With vitamin K2, you may be deficient your whole life and be none the wiser. Disorders that could be caused by a lifelong K2 deficiency – osteoporosis and atherosclerosis primarily – are often attributed to other factors, like diet and exercise.
K2 indirectly activates enzymes that are responsible for transporting calcium in the body. Specifically, it’s a cofactor for K-dependent carboxylase, which is itself an enzyme that alters the structure of two other enzymes: osteocalcin and matrix gla protein (MGP). Osteocalcin draws calcium into bones and teeth, while MGP removes calcium from arteries and veins, where it can accumulate in plaques. Without K2, these proteins remain in their inactive (under carboxylated) form, and calcium ends up in unwanted places (contributing to atherosclerosis) and not in the places we need it like bones (contributing to osteoporosis).
Luckily, K2 is found in delicious things like egg yolks, butter, and cheese. But these foods have to come from animals well-fed with green plant matter; butter from grain-fed cows and eggs from grain-fed chickens are likely not rich sources of K2. I do try to buy free-range eggs (though they rarely advertise the chicken’s diet) and grass-fed ghee, and I suppose that supplements are always an option. But the book highlights the best dietary source of vitamin K2 – natto – accompanied by a rather descriptive passage about how terrible tasting/smelling/feeling it is.
Natto is fermented soybeans, along the same lines as miso, tempeh, and soy sauce, all of which have fairly distinctive flavors. But Natto’s distinctiveness is on a whole other level. It comes in smallish servings inside little styrofoam packages, with soy sauce and mustard as suggested condiments. There are two things you notice about it before it even touches your tongue: the smell, and the stringiness.
Natto is fermented by a particular microorganism called natto bacillus. Legend has it that natto was discovered when a group of soldiers, carrying soybeans in a straw sack, were ambushed, and forced to abandon their food sacks. When they returned, the beans had been fermented by bacteria living within the straw. But having no other food at hand, they were forced to eat it; and rather than being totally disgusting, they evidently found it quite agreeable, and thus natto was born. There may be some truth to this story: natto bacillus is a strain of bacillus subtilis, which (according to wikipedia) is also known as grass or hay bacillus.
One of my coworkers spent a co-op term working in Japan, and one day at lunch I asked him if he had ever tried natto. This led to a dialogue which ultimately culminated in the creation of a Natto Challenge, in which he offered to bring some to work the next week for us to try. So on the following Tuesday we had three little styrofoam containers of the stuff in front of us.
First impressions as the protective wrapper was pulled away from the mass of natto were that it smells awful, and kind of resembles rice krispie squares. The latter owing to the extreme stringiness of whatever starchy byproduct of the fermentation process holds the beans together. It was seemingly impossibly to get some natto onto your utensil and up to your mouth without a few string clinging in an unsightly manner to your face.
I’m not going to lie, I found it fairly unpleasant at first. And adding the sauce and mustard didn’t help much. And disappointingly, the taste seemed to get worse the more you ate, not better. As the coop student sitting beside me finished his portion, I was determined to choke down every last bean of my own, though it required a large glass of water and some duck-like swallowing maneuvers to do so.
It seems some people have a natural taste for it, enjoying it daily with rice as a breakfast food. I wouldn’t go so far as to say I had a natural taste for it, but I didn’t find it quite as repulsive as I had anticipated. It wasn’t tasty, and I would say it had a slight unpleasant taste. But the unpleasantness is mild and not overpowering. By itself, it’s not something I would want to eat with any frequency. But its mildness leads me to believe that when paired with stronger (and more tasty) flavors, it could become something I wouldn’t mind eating for health purposes. I’ve read that you can trick yourself into developing a taste for initially unpleasant flavours (like the bitter tastes of coffee or beer) by associating them with calorically dense meals. Your brain is like “Hey, this taste means I’m going to get lots of calories – I’m going to make you like it so that you’re more likely to seek it out”, or something like that.
Thus today was Natto Challenge day 2, and I must say it was a success. Big A and I have had a new favorite snack of late, thanks to the appearance of conveniently packaged seaweed snacks at Costco. We take some rice, add a sliced avocado, crumble some seaweed sheets into it, and finish it off with a splash of soy sauce. It’s like deconstructed vegetarian sushi, and it’s super tasty. I decided these strong flavors might mesh well with the mild natto taste. So I mixed some natto in with warm rice, tossed in the other ingredients and voila:
It wasn’t bad. The characteristic natto flavor was really subtle. Granted it wasn’t as tasty as our original natto-free version of this snack, but it was still good. I’ll definitely eat it this way again. I’m curious to see if natto could be worked into a sweet dish as well, or maybe pureed and used in something like pancakes.
And just in case Operation: like natto doesn’t succeed, I’ve ordered some K2 supplements from my favorite online health store, iherb.com.