by Shant Mesrobian

At some point during the last decade, while living in Washington D. C., I began to suffer from hand eczema. Painful red itchy inflamed dry skin covered most of my hands. It was usually triggered by cold dry weather in the fall and winter. It also flared up after a lot of cleaning — when my hands were exposed to a lot of water and soap, which dried them out. I was in my twenties when it began.

Eczema, also called atopic dermatitis, is believed to be a too-extreme allergic reaction. It is common. About 10% of American adults suffer from it, according to two recent surveys (here and here). In my case, a certain level of dryness is required. I believe the dryness, which may reduce a protective coating, allows something in the environment, like dust or pollen, to trigger an allergic inflammatory response.

The first thing I did to solve the problem was see a dermatologist, who prescribed a steroid-based cream. The cream did reduce the inflammation. It was just something to apply when the inflammation appeared. It didn’t stop it from happening. As I learned more about eczema, I decided this was an absurd solution. Steroids have nothing to do with the cause of eczema. At best they treated the symptoms, and had bad side effects (is anything creepier than “skin thinning”?).

Then a funny thing happened. A few years ago, my eczema disappeared. I didn’t notice it had stopped until this fall (2013), when it came back. I had forgotten about it. As soon as the weather turned cold and dry, it hit hard.

Why had it disappeared and returned? My environment had not changed in any big way. Nor, when I first thought about it, could I think of any dietary changes in the past year or two. Then I realized I had made a dietary change – and recently. In September (2013), I had stopped eating a few fermented foods that I had steadily eaten for the past few years — sauerkraut, kimchi, and kombucha. I had drank kombucha only a few times a month but had eaten sauerkraut or kimchi almost daily (3-4 forkfuls/day, $0.50/day). I had started eating them in 2011, hoping they would improve my health. The last time I had had eczema was the winter before I began regularly eating them.

Had the fermented food prevented eczema? This was not far-fetched. The ideas that (a) bacteria in food can influence your immune system and that (b) bacterial exposure can “calm down” an over-reactive immune system are both well-accepted. Review articles are here, here and here. There is lots of supporting evidence. An early example is the evidence behind the hygiene hypothesis – children in “dirty” places had fewer allergies than children in cleaner places. This article says “approximately 70% of the entire immune system” is in the gastrointestinal system.
Fermented vegetables like sauerkraut and kimchi are dominated by the bacterial species Lactobacillus plantarum. If sauerkraut and kimchi had prevented eczema, it was probably due to L. plantarum.

After multiple flares over a few months, I tested this idea. I found a probiotic supplement (Jarrow Formulas Ideal Bowel Support) solely composed of L. plantarum. Then I waited for my eczema to flare up again. When it did (early January 2014), I began taking the supplement (one pill daily, $0.50/day). Within three days, the eczema had completely disappeared. In the past, three days after it started the eczema got worse. It usually lasted about two weeks from start to disappearance. I had never seen it disappear like this. Usually at this point (3 days after it started) hand washing would be painful and make it worse. Now I could hand wash with abandon. Even more amazing: I could walk around outside during a cold spell without gloves, and did not have any exacerbation or return of symptoms. Being able to do these things three days into a flare up had never happened before.

I kept taking the supplement (one pill/day). In the past, before the fermented foods, I had at least some inflammation on my hands through the entire fall and winter, with extreme periods and less extreme periods. Now (February 2014) I have zero inflammation. In the past, dryness on my hands immediately led to inflammation. In normal people, dry hands are dry hands. I never have just dry hands. Dryness is a trigger. I’m not used to seeing a dry hand without inflammation on it. For the past few weeks, I’ve had mildly dry hands without inflammation. I’ve become a normal person with dry hands.

Several studies – which I didn’t know about when I saw that the probiotic supplement helped — support the idea that L. plantarum can reduce eczema. Two studies (here and here) found that L. plantarum inhibited house-dust-mite-induced eczema in mice. Another study found that L. plantarum inhibited allergic reaction and histamine-induced scratching (itching is a hallmark symptom of eczema) in mice. It concluded that L. plantarum “may improve allergic diseases, such as . . . atopic dermatitis”. In another mouse study, L. plantarum was successfully used to reduce dust mite allergy. The most impressive evidence was from a 2012 study done with children in South Korea. All of them had eczema. Those given L. plantarum improved much more over 14 weeks than those given a placebo.

In contrast to my success, many studies have found no effect of probiotic supplements on eczema. One review concluded “Initial meta-analyses suggest no benefit of probiotics [supplements] in the treatment of eczema or asthma.” Maybe they tested the wrong bacteria or used a too-small dose. I haven’t noticed any effect of yogurt (which contains different bacteria) on my eczema.

After I posted about this in my blog, several people tried something similar and reported what happened. Overall I would summarize their results as modest improvement. The most positive result was this: “After 5 days of radish kimchi the eczema in that person [a family member] is very clearly receding and, in a few spots, is completely gone. From prior experience, it would not have done this on its own.” The least positive result was no change, which a few people noticed.

My interpretation is that kimchi and sauerkraut – that’s what everyone tried — have far less L. plantarum than the probiotic supplement I took. This article considered sauerkraut “probiotic” when the concentration of L. plantarum was “higher than 10^6 colony-forming units (CFU) per gram of product”.
This sauerkraut maker says their sauerkraut has 8 x 10^6 CFU per gram. A serving of sauerkraut might be 60 g, so the total number of L. plantarum in one serving will be roughly 5 x 10^8. In contrast, the probiotic supplement I took supposedly contained 10^10 CFU – a factor of one hundred more. A daily dose of 5 x 10^8 CFU might eliminate eczema if you eat it for months, as I did, but might produce much more modest results after just a week.

Someone commented:

I had awful adult acne, hideous cystic lumps that left scars. My college pictures are hard to look at. This continued into late twenties. It was [due to] a food allergy [that] took forever to figure out: black tea. Especially Oolong. [Oolong and black tea are usually distinguished. Black tea is “fully-fermented”, oolong “semi-fermented”. — Seth] My face would begin to itch within minutes of drinking, and the breakout came the following day. But it took years to notice the connection. . . . Green tea is no problem. Coffee is no problem.

In response to my questions, he verified the connection:

On Tuesday night, I drank two cups of strong black tea. Itching began within a hour, and mouth sores hit 18 hours later. Now at 48 hours, very slight acne breakout, but not bad at all.

Part of figuring out the problem was realizing that face itching was a bad sign. The black tea –> itching connection was relatively easy to notice. Another difficulty was the wrong ideas he’d been taught:

To figure out the tea, I first had to unlearn things that turned out to be wrong. Unlearning seems to be much slower than learning.

First, when I was in high school, acne was widely considered to be partly a hygiene problem. So I spent vast useless effort washing several times a day, while possibly missing signals that the cause was something else. Later, in college, I tried washing my face only with water, and then not at all. This turned out to have no effect on acne. That was the first clue of wrong learning.

Second, in high school I drank a lot of grapefruit juice. The citric acid was extremely painful on the mouth sores. I somehow concluded, maybe just emotionally biased by the sharp pain, that grapefruit juice was causing the sores. In college I didn’t drink grapefruit juice, but there was no effect on mouth sores.

Third, a received wisdom was that acne is hormonal, and there was not much you could do but try to manage it. So I didn’t even try to look for an environmental cause, until I was still suffering from acne well into my twenties.

These three wrong conclusions probably cost me years.

Not to mention the astonishing claim of dermatologists that acne is not caused by diet. This list of what to do about acne from the American Academy of Dermatology says nothing about food. It is plausible that in this situation — in 2014, after hundreds of years of experience treating the problem and thousands of medical journal articles about it — the overall effect of doctors is to make things worse.

• Sugar for insomnia
• Japanese pickle prevents flu in mice
• Interview with Edward Jay Epstein
• contact lenses that measure blood sugar
• Duke University blunders badly in China. No one wants to attend its new campus in Kushan. A friend of mine called the campus a “real-estate scam”.

Thanks to Phil Alexander, Joseph B. and John Batzel

At a recent dinner, Steve Hansen, a friend of mine, said the difference between his current teaching and earlier teaching is “night and day,” partly due to this blog. I asked him to elaborate.

ROBERTS What is your teaching situation?

HANSEN I’ve been teaching at Peking University [in Beijing] in the Guanghua MBA program for the last two years. I teach courses in innovation (big company Clayton Christensen sort of stuff), entrepreneurship, and social responsibility/social enterprise. The classes usually consist of 30-50 students from all over the world.

My teaching at Peking U. is a part-time job. Full-time I run a social enterprise here in Beijing (Phonemica). Before this I was a professional market researcher working at a large company and I worked as a consultant for years. Although I had a little teaching experience early in my career (e.g. taught undergraduates when I was a grad student), I certainly did not have any special teacher training or background. I was hired at Peking U. on the basis of my professional experience. Thus when I started teaching I was to a large extent repeating to my students the experience I had had as an MBA student myself, years ago.

ROBERTS How did you teach this course at first?

HANSEN My teaching changed quite a bit in the first year. The first semester I did lecture and discussion. I didn’t like it. I felt it was a lot of work to prepare, and while it helped me personally a lot, by getting me to summarize my learnings from years of reading and work experience, I didn’t feel it gave the students a lot. Even though the course got mildly positive reviews, I felt the students weren’t engaged in a way that made me excited about going to teach.

The second semester I started making changes. First, I took to heart some advice I got to follow more of a case study approach. The experience I gave the students in the beginning of that semester was fairly standard “case study” method made famous by Harvard. Here‘s a mini-documentary of how Harvard expects case study method to work. The professor asks pointed questions from the case and expects the students to have answers and defend them.

ROBERTS What caused you to change how you teach it?

HANSEN I like the case study method in theory. I like it a lot. I think by mimicking real life situations and summarizing the many facts that synthesize a business manager’s knowledge and must be put to use in making business decisions, the case study method has the potential to help students learn in a way that is useful: giving them the skills to make real-world decisions, and doing it faster than they could get the same experience by going out and working. As far as activities that can be done in an academic environment go, the case study is pretty darned close to “learning by doing”.

However, I found my classroom reality was different from the ideal portrayed in that Harvard Youtube video, in which a professor says, “I have been amazed… at the consistent level of high preparation”.

In my reality, students often didn’t come prepared. Sometimes they would say, “Sorry, I didn’t have time to read the case” — despite significant portions of the grade being dependent on in-class participation. And even if they were prepared, to some extent, often it wouldn’t be to the extent that I had hoped, where they were able to argue the intricacies of a position and defend it. Instead they might give a cursory answer, with a weak defense, and much of the class would be spent with me pushing them to elaborate their answers through Socratic questioning, lecturing, and so on.

So I was still doing a lot of the talking, and really leading the class. It was better than my first semester, but it wasn’t meeting my standards of what a real learning environment should be: student-led because they’re motivated to learn.

It was about at that time that I must have read some of the articles and ideas you published about “learn by doing”. Those rang true to me. Learning by doing is something I’ve always believed in and tried to practice, and I realized that my students still weren’t doing it.

So later during that semester I started experimenting. My first experiment, I’m sorry to say, was a complete failure. My approach for a few classes was to have students simply teach the class. I would assign the next class’s case study to a group. They would read the case and come up with main points. I would meet with them and review what they were going to do. Then they went in and tried to teach their fellow students.

In retrospect it seems obvious that this was wrong. As business school students the “doing” that I wanted them to do shouldn’t have been to “do teaching” but to “do business” as simulated in the case. When the students were teaching the case they were (again naturally, in retrospect) worse than I was. They would lecture rather than ask. They would miss key issues. And of course they had the same problem I’d noticed myself: other students weren’t prepared enough, even though the lecturing group was extremely prepared.

After enough experimentation to realize this wasn’t working, I cut it off and went back to my semi-successful case study method.

But the failure had given me an idea. I saw that students who were forced to present were MUCH more engaged than those who sat and listened. Why not, I thought, just make everyone present? It would kill several birds with one stone. First, I’d noticed that students’ presentation skills needed a lot of work. They had trouble being concise and answering the critical questions. Having to present would give them practice on this critical skill. Second, they’d be engaged and motivated — at least for the part where they were presenting. Third, by divide-and-conquer of the case itself, we’d get far deeper into the details and (sometimes) quantitative analysis of the cases.

And so that’s what I started doing this year. It has worked even better than I imagined. Not only are students engaged for their part of the lecture and discussion; the preparation seems to spill over into the whole case, so most students really know what’s going on. The presentations get better and better as the semester progresses. In contrast to the past, now I’m having to shut down vigorous discussions in the interest of time, rather than ask pointed questions to stimulate interest. And best of all, this environment satisfies my own desire of creating a place where students want to learn. I work less, and the students learn more. That’s the part that seems “night and day” to me.

For anyone who’s curious, there are some details I’ve worked on to make the approach better, at least for my particular situation. Here’s the nitty gritty:

I divide the class into random groups of 4-5 students. That group is together for the semester, and for each class they’re tasked with presenting on one part of the case. I assign that presentation the week before, and it’s often a question that forces them to take a position. Often, too, I assign the same question to two different groups. This has the effect of creating a sort of debate between the groups, because they almost never come up with the same answer to a question.

I require VERY short presentations. Usually 2 minutes. Sometimes 3 or 4 if the topic is very complex. I allow any member of the group to present. Although I encourage them all to take the opportunity to practice presenting, I don’t force the issue.

All the students in the group get the same grade, but with the following “peer evaluation” element that I adapted from someone else (i read about it online but have now lost track of where). Peer evaluation means that your fellow students give you a grade at the end of the semester. If your fellow students all give you 100%, then you get 100% of the group grade. That’s the usual case. On the other hand, if all your fellow students give you 50%, that probably means you didn’t do much and you get only 50% of the group grade — a guaranteed failure for that portion of the class. In even more detail, what I do is take the average of the peer scores, but not including the lowest score. This virtually eliminates the possibility that one enemy classmate can sabotage a groupmate’s grade.

Overall I’ve found that the peer evaluation mostly eliminates the freeloader problem that general plagues groupwork. In cases where someone tries to freeload, they simply get a bad grade, so the other groupmates aren’t really bothered about it.

At least as importantly, this entire system, once explained, makes my grading job much easier.

I also like the “group is responsible for the presentation” approach because it allows some flexibility. There’s always going to be a week during a semester that a student simply gets swamped with other things and doesn’t have time to prepare. Under the group presentation regime, the busy students can beg groupmates to cover for them, and then return the favor another week. Would it be better if everyone were always prepared for every class? Well, maybe, but that doesn’t really seem realistic.

ROBERTS What did you read that influenced you?

HANSEN I read all your posts about education and teaching. It’s hard to say any one post made me change the way I teach. It’s more that your posts about teaching, like your posts about diet etc., often help me consider what my goals are and how I can do low-risk experiments to find better ways to reach those goals.

As for specifics…

I remember reading this, for example, that helped me remember to think about my students’ goals rather than my own for them (not that I think I should have no influence on their goals — more that I should keep in mind they are autonomous agents about whom I know little and should learn more).

I still grade, but I’ve experimented with “grading less” I guess you could call it, partly inspired by discussion like this.

I was probably most influenced/inspired by the Halmos paper (also here) you mentioned. I was a math major as an undergraduate, so I liked the subject matter. I was always interested in the kind of simple statement of problems and choices that he describes in that paper, not just in math, but in business and elsewhere. I really enjoy simple problem statements that force one to go through complicated analyses and yet still reduce everything back to a simple statement of resolution. Business at its most interesting can be quite like that. You have to make decisions: fund this project or don’t. Build this product or build that one. What do you do?

Even more than enjoying the problems, though, I completely agree that the hard part is making students ask questions. It’s not actually solving the problems that’s hard; it’s figuring out what the problems are in the first place. After reading his paper, I started doing some searching and found others who were experimenting with teaching techniques. It would take me a while to re-find those people, but I definitely gleaned ideas from others. These helped shape my own experimentation.

• Probiotics for colicky babies
• Edward Jay Epstein on diamonds (video). “I bought a diamond for $1500. A day later I tried to sell it. People were offering me one-fourth or one-fifth the price.”
• Internet spreads much better treatment for clubfoot
• Marion Nestle, an NYU professor and frequently-quoted food expert, says it is a “myth” that “what you eat is more important than how much you eat.” The concept of a body-weight set point was first proposed in about 1950.

Thanks to Carl Willat.

Many researchers were shocked when a large 1984 experiment found that a beta-carotene supplement increased lung cancer. Because beta-carotene is a potent antioxidant, and epidemiology had linked eating vegetables with less cancer, it was supposed to decrease lung cancer. My Berkeley neighbor Bruce Ames was the foremost proponent of the idea that antioxidants will decrease cancer.

Now more evidence supports the idea that antioxidants may increase cancer.

A request for comment elicited this:

“It’s disappointing but not surprising that people’s beliefs are not modified by scientific evidence,” said Dr Paul Marantz, an epidemiologist at Albert Einstein College of Medicine in New York. “People so want to believe there is a magic bullet out there.”

One commenter on the article rightly says:

“It’s disappointing but not surprising that people’s beliefs are not modified by scientific evidence,” . . . Rather a snide comment considering the fact that it was science that spent years telling everyone that antioxidants and supplements were beneficial.

 

A few years ago, two studies found that people with sleep apnea have a much higher rate of cancer than people without it, even controlling for several cancer-related variables. In one study, the increase in risk was five-fold. These studies raised several questions: 1. Were the associations due to chance? 2. If real, did the associations reflect cause and effect? Surely people with sleep apnea are different in several ways from people without it. 3. If the associations did reflect cause and effect, which of the many effects of sleep apnea was/were responsible?

A new study found that rats woken up frequently got more cancer. This is a correct prediction from the idea that bad sleep increases cancer, increasing the plausibility of that idea.

[The study] used mice, housed in small groups. During the day—when mice normally sleep—a quiet, motorized brush moved through half of the cages every two minutes, forcing those mice to wake up and then go back to sleep. The rest of the mice were not disturbed. After seven days in this setting, both groups of mice were injected with cells from one of two tumor types (TC-1 or 3LLC). All mice developed palpable tumors within 9 to 12 days. Four weeks after inoculation the researchers evaluated the tumors. Tumors from mice with fragmented sleep were twice as large, for both tumor types, as those from mice that had slept normally. A follow-up experiment found that when tumor cells were implanted in the thigh muscle, which should help contain growth, the tumors were much more aggressive and invaded surrounding tissues in mice with disrupted sleep.

Great Sleep! Reduced Cancer! is a whole book (98 pp) about the connection between sleep and cancer.

Epidemiologists haven’t yet figured out that they should always measure sleep quality, just as they always measure cigarette smoking and body weight, but at least interest is growing. Both short and long sleep are associated with a higher risk of heart disease.

 

 

Philip Seymour Hoffman, the great actor, was found dead a few days ago with a needle in his arm. Last year, Cory Montieth, the actor, died in similar circumstances. Why did they die? It was hardly the first time they’d taken heroin.

Starting in the 1970s, Shepard Siegel, a psychology professor at McMaster University, did a series of rat experiments that showed that drug tolerance and craving involved a large amount of Pavlovian conditioning. Repeated exposure (e.g., injection) of Drug X in Situation Y (e.g., your bedroom at 11 p.m.) will cause learning of an association between X and Y. This association has two effects. First, when exposed to Y, you will crave X. Second, when you take Drug X in Situation Y, the effect of the drug is diminished. You become “tolerant” to it.

You have probably experienced both effects — they occur with caffeine, chocolate and alcohol, for example — but are unaware of Siegel’s explanation: Situation-drug associations. After you learn the association, Siegel said, the situation generates a response in your body that opposes (reduces) the drug effect. If the drug makes you less sensitive to pain, the conditioned response is more pain sensitivity. If the drug makes you awake, the conditioned response makes you sleepy. It’s easy to realize that drug craving involves associative learning: You notice that you crave coffee or whatever in familiar situations but not unfamiliar ones. You crave Drug X at college but not at home. It’s much harder to grasp that the tolerance involves associative learning.

Drug users, such as Hoffman and Montieth, as they become “tolerant”, take larger and larger doses, not realizing that their “tolerance” depends on a learned association. The situation becomes more and more dangerous because if you take the drug without eliciting the conditioned compensatory response, you may die. Without the conditioned response, a drug amount you survived yesterday may kill you today.

Siegel explored the possibility that this actually happened — that drug addicts died of “drug overdose” because they took the drug under unusual circumstances that didn’t evoke the compensatory response. He found plenty of support for this idea. One sort of support was interviews with “overdose” survivors. They often described unfamiliar circumstances at the time of the injection — e.g., there’s usually music, but this time there wasn’t. Another sort of support was a rat experiment with heroin. After developing tolerance to heroin, rats injected with a really large dose in a strange situation were much more likely to die than rats injected with the same dose in the same situation where they became tolerant.

I am pretty sure Hoffman and Montieth didn’t know about this research. There is a connection with the Shangri-La Diet. In both cases, Pavlovian learning has a big effect on something we care a lot about (life/death in the drug case, body weight in the diet case) and this connection is highly non-obvious.

A 2009 study followed about 9000 men for 10-20 years. It found that strength (how much you can bench and leg press) measured at the start of the study was associated with likelihood of dying of cancer during the study. Men in the upper two-thirds of the study population in strength had 40% less cancer mortality. This might be the most surprising result:

Further adjustment for BMI, percent body fat, waist circumference, or cardiorespiratory fitness had little effect on the association. The associations of BMI, percent body fat, or waist circumference with cancer mortality did not persist after further adjusting for muscular strength.

In other words, muscle strength was a better predictor than several similar measures (BMI, etc.) and these other measures stopped predicting when corrected for muscle strength. Muscle strength is closely connected to something important.

Men who are stronger by and large exercise more, no doubt. Yet muscle strength is determined by resistance training, not aerobic exercise — and it is aerobic exercise (and to some extent walking) that have been promoted by countless experts since the 1960s and the invention of the concept aerobic. Jogging reduces how much time you have for resistance training.

These findings interest me because I do a lot of resistance training — stand on one leg to exhaustion several times per day — purely to sleep better. By improving something easy to measure (sleep), these data suggest I have also been improving something hard to measure (chance of dying from cancer). Not surprising, but reassuring.

My data also suggest two different possible reasons for the strength-cancer association. One is that men who exercise more sleep better as a result; better sleep, better immune function, less cancer. Another possibility is that strength is a marker for good sleep. Among men who do equal amounts of exercise, those who sleep better will be stronger.

From The Breviary.