- How not to govern a university
- Smelly fish popular in Korea. “Extremely chewy texture.”
- Popular pain killer associated with doubled risk of atrial fibrillation
- Hunter-gatherer microbiome
- interview of me in Chinese
Thanks to Tyler Cowen.
Thanks to Tyler Cowen.
I found this comment from Art Ayers deep in a discussion on his excellent blog Cooling Inflammation:
Probiotic fermenting bacteria only work in the upper part of the gut, not in the colon. The anaerobic bacteria that work in the colon must be slowly acquired by persistent eating of diverse veggies to provide diverse polysaccharides and uncooked veggies to provide the bacteria.
I agree and disagree. It’s an excellent point that the bacteria near the stomach are quite different from the bacteria deep in the colon. So you need different sources of each. I don’t know what “probiotic fermenting bacteria” are (I was under the impression that all bacteria “ferment”), but, yeah, bacteria that live on lactose (e.g., in yogurt) are going to be quite different than bacteria that live on more complex sugars that are digested more slowly than lactose and thus pass further into the intestine.
To me, this explains why I like vegetables. I have no trouble avoiding fruit, bread, rice, pasta, and so on, but I hate meals without vegetables. Why? This line of thought suggests it is because they supply complex polysaccharides needed for deep-colon health. As Ayers implies, you wouldn’t need a lot. This line of thought suggests how you or nutrition scientists can decide what fermented foods to eat (some for each part of the digestive system).
I disagree about raw vegetables. Like most people, I don’t like raw vegetables. I like the crunchiness but the taste is too weak. That most people are like me is suggested by the fact that raw vegetables are almost never eaten without dip or dressing (which add fat and flavor) or something done to make them more palatable (e.g., sugar and liquid from tomatoes). If raw vegetables were important, even necessary, for health, the fact that they are hard to eat would make no evolutionary sense.
I do like pickled/fermented vegetables of all sorts, such as kimchi and sauerkraut. I believe they are a far better source of the bacteria you need than raw vegetables (they have far more of the bacteria that grow on raw vegetables than ordinary raw vegetables).
Thanks to Aaron Blaisdell and Peter Lewis.
In a review of Anna Reid’s new book, Leningrad: Tragedy of a City Under Siege, I learned that one of the calorie sources that starving Leningraders came to eat was:
‘macaroni’ made from flax seed for cattle
To which I say: Damn. The implication is that, before the famine, “flax seed for cattle”, which is roughly the same as flax seed, was considered unfit for human consumption. Only when starving did Leningraders stoop to eat it. I can buy flax seed in Beijing. But not easily.
The triangle is complete. I have now learned that the main things I care about in my diet, which I go to great lengths to eat every day, are all considered “disgusting” by a large number of people:
1. Flax seed. It is the best source of omega-3 I have found. I eat ground flax seeds every day. Flaxseed oil goes bad too easily.
2. Butter. Perhaps the most reviled food in America, at least by nutritionists. A cardiologist once told me, “You’re killing yourself” by eating it.
3. Fermented foods. Many fermented foods are considered disgusting — after all, they are little different than spoiled foods.
Thanks to Alex Chernavsky.
From a recent story in the Santa Cruz Sentinel:
[Kelly] Dearie turned to fermented foods in a moment of despair.Her husband Charlie, who suffered from an autoimmune disorder that attacked his platelets, was told by doctors that he needed a spleen removal and a hip replacement. That would mean Charlie, an active 32-year-old man, would never be able to run or mountain bike again. . . .
The family decided to seek an alternative, and consulted Santa Cruz clinical health coach Craig Lane from Health Alkemy. . . . He checked Charlie’s temperature, blood pressure and lab results, and listened to Charlie talk about his diet, sleep and exercise. Instead of the surgeries, Lane recommended some dietary changes such as taking out coffee, wheat and sugar, and adding beet kvass, a traditional Russian fermented tonic.
Within three weeks, his platelet numbers were almost normal. Within two years he was running again, said Dearie. . . . Inspired by her husband’s healing, Dearie opened Creative Cultures and sells the beet kvass.
I learned about wild-fermented wine from Shana Reade, who teaches wine sellers about wine. She works for a New York wine distributor called Empire Merchants.
Before the 1950s, almost all wines were made with wild ferments. Only then did cultured (store-bought) yeasts start to be used on a large scale. The new wines surely tasted worse, but it was the era of TV dinners. The first cultured yeasts were especially popular in Australia, where less tradition blocked their adoption.
Nowadays wild-fermented wines are made in many places, including California, France and Germany. They are more expensive than cultured-yeast wines but you can buy one as cheaply as $15. Wild yeast is free, but the overall process is more costly because it needs more space and time. When you do wild fermentation, you put out vats of wine open to the air. The vat-to-vat variability goes way up and some vats will have to be thrown out. Wild fermentation also varies much more in how long it takes. Wineries rarely harvest all their grapes at once. With cultured yeasts, but not wild yeasts, they can be sure that one batch will finish before the next batch arrives.
Scientists have found that the yeasts in wild-fermented wines have thicker cell walls than the yeasts in cultured-yeast wines. This is an example of the general observation that microbes (and other living things) grown by man have fewer functioning genes and metabolic pathways (such as the metabolic pathways that build cell walls) than the wild type. Wild yeast, of course, has a more stressful and variable environment than cultured yeast. Cultured yeast loses functioning genes over generations because it does not encounter the problem they solve. There is no selection against deleterious mutations. Because wild yeast has more functioning pathways, it produces more metabolic byproducts, making a more complex flavor. This is a tangible version of the idea that we should use all our metabolic pathways. (A better version is use as many metabolic pathways as possible — fermented foods help with that.) So wild fermentation is (a) more diverse in terms of strains of yeast than cultured yeast and (b) individual strains of wild yeast have more functional metabolic pathways than individual strains of cultured yeast. (Cultured wine yeast starter includes several strains of yeast.)
The ecology of knowledge isn’t simple. Cultured-yeast wines (in the 1950s) were made possible by earlier wild-fermented wines. With cultured yeasts you can do wine experiments you could never do with wild yeasts, thereby learning how to make better wine in general. Today’s wild-yeast wines benefit from that knowledge. They also benefit from a mass market created by cheap (cultured-yeast) wine. An ecosystem that includes both sorts of wine spreads much further and produces much better wine than an ecosystem that includes only one sort of wine.
Personal science is like cultured-yeast wine in the sense that it allows far more experiments. Personal scientists can do experiments that professional scientists would find almost impossible. (For example, the effect of standing 8 hours/day on sleep.) A scientific ecosystem that includes both personal and professional science is going to solve problems far better than an ecosystem with only one of them.
More broadly, the story of wild-fermented wines illustrates how you need complexity and optimality — not just one of them — to solve actual problems (in contrast to artificial ones). Wild yeasts are complex, but not optimal; cultured yeasts are optimal but not complex.
A well-functioning system produces both complexity and optimality. This not-very-difficult idea is almost absent from modern thought. In nutrition, economics and education, for example, there has been almost no study of how to produce complexity.
Nutrition scientists have had little interest in fermented foods, which increase our inner complexity. Yes, as nutritionists say, we need good amounts of a long list of nutrients and micronutrients (optimality). In addition, however, we need inner complexity to solve actual problems, such as digesting food and fighting off pathogens. You can’t make a list of all the metabolic pathways we need to be healthy — it might be in the hundreds of thousands. You’d never learn our need for complexity from any nutrition book, as far as I can tell.
The science of economics revolves around optimality (e.g., most profit). I believe the current stagnation of the American economy is partly due to the poor understanding of economists of how to produce economic complexity. If they don’t know, neither will anyone else. Interest groups, rich and poor, have no interest in complexity. (Illustrating The Stupidity of Crowds. The Wisdom of Crowds is about optimality.) All sorts of policies are too narrowly evaluated. Their effect on optimality is assessed (how will this affect growth of GDP? or how will this affect percent unemployed?), but not their effect on complexity.
As for education, it is a good idea to push students to be better (push them toward optimality, e.g., be better at math). But a single-minded emphasis on optimality (e.g., No Child Left Behind), with no value placed on complexity, is a disaster.
Thanks to Casey Manion and Adam Clemens.