Month: April 2009

Principles of Experimental Design

Seth Roberts7 Comments

In this 10-minute talk I discuss what I think are the two main principles of experimental design:

  1. Something is better than nothing. You learn more from doing something than from thinking about what to do.
  2. When you do something, do the smallest easiest thing that will help, that will tell you something you don’t know.

Grad students often fail to understand Principle 1: They worry too much about what to do. Early in grad school, that was my big mistake. Professors often fail to understand Principle 2: They do something more complex than necessary. Failure is much more likely than they realize. My previous post was about such a failure (using genes to predict disease). When I was an assistant professor, I often made this mistake.

Judith Krug, RIP

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Judith Krug (1940-2009) was a librarian who defended libraries with objectionable books:

The importance of her work was made clear [to her] when she read “And Tango Makes Three” to her granddaughter’s class.

The book is often the target of censors because it’s about two male penguins who “adopt” an unclaimed egg.

When she was finished, a girl she later learned was being raised by two women stood and clapped her hands.

Via Radosh.net.

Another Reason to Eat Fermented Foods

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To protect against C. difficile infection:

What is so frightening about C. difficile is that it is often spurred by antibiotics. The drugs wipe out the targeted illness, like a urinary tract or upper respiratory infection, but they also kill off large portions of the healthy bacteria that normally live in the digestive tract. If a person [who has just taken antibiotics] comes into contact with C. difficile, or already has it, the disruption to the beneficial bacteria creates an opportunity for the harmful bacteria to flourish.

The NY Times article doesn’t mention fermented foods.

Thanks to Ashish Mukharji.

Dead Food = Always the Same

Seth Roberts12 Comments

If you have two hammers, how many nails do you see?

I’m in Boston. I had planned to give up fermented foods during this trip and see what happened. Too hard, it turned out. Sitting in a diner, I wondered: where can I get kombucha? The diner sold a bunch of bottled drinks: juice and soft drinks. Foods that taste exactly the same each time, which I call ditto foods and which I believe caused the obesity epidemic. (Because their taste — actually, their smell — is so uniform, a very strong smell-calorie association can build up, making them very tasty and very fattening. Ditto foods are the laser beams of food.) I realized these drinks were exactly the opposite of what I wanted. Fermented foods, because they involve growing bacteria, are inherently more variable than other foods. It is hard to keep constant from batch to batch everything that affects bacterial growth.

Funny thing: the growth in childhood asthma and allergies, now called an epidemic, started at roughly the same time as the obesity epidemic — around 1980. Around 1980, people started to eat a lot more fast food, snack food, and microwaved food (from packages). All ditto foods. All bacteria-free. In home cooking, I think fewer precautions are taken to wipe out all bacteria. You eat what you’ve made soon after cooking, whereas factory food might be eaten weeks or months after production. So factory food has preservatives — and I think the result is overkill, just like antibiotics.

Looking at the food I could buy in Boston was like looking at a post-apocalyptic landscape. Dead food everywhere. Supermarkets, diners, fancy restaurants. Dead food is uniform food; food manufacturers had bludgeoned their products into uniformity. At a Cordon Bleu cooking school, judging from promotional literature, not a word is said about fermented food. In advanced-thinking Cambridge, which you might think would support fermented foods, I found only two stores that sold kefir and only three that sold kombucha. Many people complain about what they call “processed food” but the actual problem is food not processed enough (by bacteria). A better complaint would be about dead food.

I suspect fermented foods are avoided by commercial food makers not only because they are more variable than other food and contain scary bacteria, but also because they are more expensive to make: They require more space and time. The stuff must sit somewhere, taking up space, for days or even weeks, while it ferments. At home, it’s easy: You make it and put it somewhere, and go away and do something else. In a factory devoted to making food, there is nothing else to do and no free space. The monoculture problem.

To (Not) Catch A Thief

Seth Roberts3 Comments

This short article about Edward Skyler, Deputy Mayor of New York, mentions four times (headline, led, body, final quote) that he tackled a mugger. I have a similar story. Had I known it was so interesting . . .
I was in Paris — same trip that inspired the Shangri-La Diet. It had been raining, the streets were wet. I heard a shout: Stop that man! A man came running toward me. I tried to stop him but I slipped on the cobblestones and fell in front of him. Perfect tackle. Lying on the ground, he asked: Why did you do that? Nobody came. He got up and ran off.

As I walked away a woman came up to me. “Are you okay?’ she asked. A man said to me,”That was unusual what you did.” I felt really good for an hour or so.

I was stunned how good I felt. I had accomplished nothing — the thief wasn’t caught. Nor was there any obvious reason I should care what two bystanders thought of me.

The lesson I drew was this. Praise alone won’t make you happy. Accomplishment alone won’t make you happy. But their combination — praise for a genuine accomplishment, however small –is enormously potent. If I’m right, a teacher has enormous power to help his students by praising them for what they do right.

Rejuvenation Company (interview)

Seth Roberts5 Comments

I sampled four brands of kombucha available in Berkeley; my favorite was from Rejuvenation Company. They are in Emeryville, which is close to where I live. “Can I visit your manufacturing facility?” I asked. The answer was no, but they were happy to be interviewed. So I interviewed Chris Campagna and Jerry Campagna, who are the company’s two employees. Before the interview I discovered they also made the rejuvelac I’d bought after a reader of this blog recommended it (“When I was a database administrator at Whole Foods, I used to drink it daily and never felt better”). Those are their two products: kombucha and rejuvelac.

How did your company begin?

It was started in 1983 in San Francisco by Dennis Campagna [Jerry’s brother, Chris’s uncle]. He was a health-food fanatic, a die-hard vegetarian, and a hippie. Now retired. He is ten years older than Jerry, but , Jerry says, looks younger.] At the beginning, he sold several health-food juices, such as carrot juice and wheat grass juice, but he also sold Rejuvelac. That was the part of the product line that’s lasted. He made them in a shared kitchen. Back then, there were dozens of small health food stores in San Francisco. It was a one-man show. Dennis drove around to them.

What’s rejuvelac?

A fermented grain drink. We use wheat. You sprout wheat berries with water, ferment them for a while, then strain out the wheat berries. We’re the only company we know of that sells it.

Why do your products say “Keep Refrigerated”?

The Health Department wanted it. For years and years, they sat store shelves, not refrigerated.

When did you start making kombucha?

Five years ago. Dennis added it to his product line. It took a few years to catch on. He’d been making it for himself for years — making it, drinking it, giving it to friends. We’re tiny players in the kombucha market. Synergy is the big player. Maybe there are 10-15 manufacturers around the country, it’s hard to know the exact number. There’s no Kombucha Manufacturers Association. Some commercial kombuchas are pasteurized; look on their websites to find out which ones. [Kombucha Wonder Drink is pasteurized.] Our kombucha isn’t pasteurized.

How has the business changed?

It used to be lots of mom-and-pop stores. The people who owned the store ran it. They recommended stuff to their customers. The customer would come in with a health problem, the owner would say, “Why don’t you try this?” Now Whole Food dominates. The emphasis has changed. The buyers want to know: Will it sell? As opposed to true quality. Nowadays, the main way we spread is that someone buys our products on a trip to San Francisco and goes home and sends us email: Where can we get it? We say: If you really want it, go to your store manager and tell him. You have a tremendous amount of clout. They listen to you. It often works out that we get a store out of that deal. We don’t do internet sales.

Over the last five years, our sales have grown a lot. Five years ago, we were mostly in San Francisco, mostly in small stores. Around 20-30 small stores. Now we’re in roughly 100-120 stores. It’s hard to have a store locator on our website because distributors don’t want to tell us who they deal with. [Their store locator page.] In the Bay Area, we’re sold at Whole Foods, Berkeley Bowl, Rainbow Grocery, plus smaller stores. In Santa Cruz, at Staff of Life. We’re moving into Whole Foods in Los Angeles, Seattle, and Portland. Pretty soon you should be able to get it in any Whole Foods on the West Coast.

What do your customers say?

A year ago, we got a phone call from a woman in San Francisco. I’m moving to Utah, where can I buy your product? Eight years earlier, she’d been sick. [Digestive problems, apparently.] Her doctor had given her antibiotics. She didn’t get better. She was given more antibiotics. Still didn’t get better. This went on for several months. She couldn’t eat anything. Even baby food would make her gaseous. She was turning ashen, suffering from malnutrition. Then she got a small bottle of rejuvelac. Just 30 minutes after drinking it, she felt a little better. She’d been drinking it regularly for eight years, didn’t want to be without it.

The Wisdom of the Five-Year-Old Picky Eater

Seth Roberts16 Comments

Children are notoriously picky eaters. Could they be trying to tell us (adults) something? Such as how bad our diet is?

Alex Combs, a stay-at-home dad and equity trader who lives near Philadelphia, has a five-year-old son whom Alex describes as “a picky eater.”

His son will not eat rice, potatoes, and pasta. He will eat small amounts of meat.

Yet his son will eat pickles, balsamic vinegar, and old/stinky cheese (but not regular cheese).

This is a fair description of what I eat! No simple carbs, some meat, plenty of fermented foods. While lots of people advocate low-carb diets, only a few, including me, advocate large amounts of fermented food. His son’s counter-intuitive liking for such gourmet “adult” foods as pickles, balsamic vinegar, and old cheeses, all high in bacteria, puts the picky eating of children in a whole new light. They’re not picky — they’re smart.

History Repeating Itself: Fear of Bacteria

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In the late 1800s in the United States, babies started developing scurvy; there was a veritable plague. It turned out that the vast majority of victims were being fed milk that had been heat treated (as suggested by Pasteur) to control bacterial disease. Pasteurization was effective against bacteria, but it destroyed the Vitamin C.

From a history of nutrition. Now children are probably getting all sorts of immune disorders, such as hay fever, for the same core reason: fear of bacteria.

The Hygiene Hypothesis (continued)

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In this NY Times Op-Ed, Jessica Snyder, author of Good Germs, Bad Germs, agrees with my comments about the hygiene hypothesis:

In 1989, an epidemiologist in Britain, David Strachan, observed that babies born into households with lots of siblings were less likely than other babies to develop allergies and asthma. The same proved true of babies who spent significant time in day care. Dr. Strachan hypothesized that the protection came from experiencing an abundance of childhood illnesses.

Dr. Strachan’s original hygiene hypothesis got a lot of press. . . Less publicized was the decade-long string of follow-up studies that disproved a link between illnesses and protection from inflammatory disorders like allergies and asthma. If anything, studies showed, early illness made matters worse. . .
Still, Dr. Strachan’s original observation was confirmed — as a group, babies in large families and day care are less likely to develop allergies and asthma than are children born into smaller families and kept at home. The same protective effect can be seen in children born on farms and in areas without public sanitation.

But the link isn’t disease-causing germs. It’s early and ample exposure to harmless bacteria — especially the kinds encountered living close to the land and around livestock and other young children. In other words, dirt, dung and diapers. Just as disease-causing microbes clearly bring on inflammation, harmless microorganisms appear to exert a calming effect on the immune system.

No mention of fermented food.

Thanks to Michael Bowerman.