Assorted Links

The Glacially-Slow Conquest of Scurvy And Its Relevance to Modern Life

Scurvy is a disease of civilization because you need civilization to make long ocean voyages. It is the first disease of civilization to be understood and eliminated. In a paper called “Innovation and Evaluation” (gated), Frederick Mosteller, a professor of statistics at Harvard, noted how long it took. In 1601, James Lancaster, a sea captain, did an experiment involving four ships on a long voyage. Men on one ship got lemon juice, men on the other three ships did not. The men given lemon juice were far less likely to get scurvy. In 1747, James Lind, a doctor, compared six purported cures for scurvy. Lemons and oranges (one cure) were much better than the other five (as Lind expected). In 1795 the British Navy started using citrus juice regularly and wiped out scurvy on their ships. In 1865, the British Board of Trade recommended citrus juice for commercial ships. It took more than 200 years for a simple and effective remedy — discovered before Lancaster — to spread widely.

The sailors at risk of scurvy did not control what they ate. The people who controlled what they ate never got scurvy. Sure, the people who controlled what sailors ate did not want them to get scurvy (high rates of scurvy were a big problem) but they also had other concerns. The lesson I draw from this story is do not let anyone else (doctor, expert, etc.) solve your health problems for you. Sure, other people, as part of their job, will sell you something, provide advice, write a prescription, provide therapy, do surgery, whatever. It might work. They want to help you — the more they help you, the better they look, the more business they attract. But it is entirely possible, this bit of history teaches, that they are slow on the uptake or have conflicts of interest and a much better solution is available.

Thanks to Steve Hansen.

More Examples of Mainstream Health Care Ignoring the Immune System

In a recent post I made an obvious point. If our immune systems were stronger, we would need antibiotics less often and antibiotic resistance would become less of a problem. I hadn’t heard this point made (for example, this WHO report fails to say it). This was one example, I said, of how mainstream health care ignores the immune system. Perfectly obvious things, such as this idea about antibiotic resistance, fail to be noticed. I gave five more examples. Since then I have come across even more examples:

1. Hospitals do little to help patients sleep and often interrupt sleep, Nancy Lebovitz pointed out (better sleep –> better immune function). This article describes the problem. One way to improve hospital sleep — beyond don’t wake patients up — would be to provide exposure to strong sunlight-like light in the morning and prevent exposure to sunlight-like light after dark. I found that an hour of sunlight or similar light from fluorescent lamps in the morning improved my sleep. Most fluorescent light resembles sunlight (both have strong bluish components), incandescent light (reddish) does not. Until they install dual lighting systems (bluish light during the day, reddish light at night), hospitals can provide blue-blocker glasses to wear after dark.

2. The book Immortal Bird (sent me by the publisher) tells how Damon Weber, born with a defective heart, had a heart transplant when he was a teenager. After the transplant, problems arose. The doctors involved (at NewYork-Presbyterian ­Hospital/Columbia University Medical Center) took the problems to be signs of transplant rejection. In fact they were due to infection. Drugs given to deal with the mistakenly-assumed rejection suppressed Damon’s immune system. They reduced his ability to fight off the infection and he died. The author of the book, Damon’s father, sued the doctors and hospital for malpractice. The doctors did not exactly “ignore” the immune system, but they apparently failed to fully grasp the danger of immune suppression, even though the infection that killed Damon is common in transplant cases. (Although Columbia Presbyterian charged half a million dollars for the transplant, “three years into the lawsuit the [hospital’s] medical director claimed Damon’s post-op records couldn’t be located.”)

3. I asked a UCSF medical student what she’d been taught about the immune system. “We cover it!” she said. In a section called “Infectious Disease, Immunology, and Inflammation”. What makes the immune system work better or worse? I asked. “If you’re stressed out, it doesn’t work well,” she said. If you’re malnourished, like in Bangladesh. You need “nutrients and vitamins”. (A booklet I got telling me to take less antibiotics told me to “eat healthy”.) She also said the students get entire lectures on how to treat diseases so rare they might never be encountered. There is a whole section on genetics. Sure, they cover it. So superficially that they don’t remember the most basic idea: Better sleep –> better immune function. I said our health care system is built around first, let them get sick. That’s right, she said. Ignoring the immune system is an excellent way to allow people to get sick.

4. Melissa McEwen pointed out that proton pump inhibitors, such as Nexium, reduce the body’s ability to fight infection. They are prescribed for acid reflux and reduce how much acid the stomach makes. Because stomach acid kills bacteria, there should have been far more concern about their safety. “Proton pump inhibitors (PPIs) are among the most widely prescribed medications worldwide [billions of prescriptions]. . . . The collective body of information overwhelmingly suggests an increased risk of infectious complications,” says this article. Because the drugs are so common, the damage is great and, because of more infection, not restricted to those who take them. It could have been avoided by research into treatments that do not harm the immune system.

What to Do About Antibiotic Resistance? Improve Immune Function

I recently got a flyer from my HMO. “Feel better soon . . . without antibiotics!” said the front page. “Antibiotics do not kill viruses” said the second page. Apparently the point of the flyer is to reduce antibiotic usage. I am surprised that doctors need protection from patients asking for antibiotics for viral diseases.

Antibiotic resistance is a problem, yes, but the bigger problem is how those who run our health care system ignore the immune system. Here are examples:

1. The historical solution to the problem of antibiotic resistance has been to develop new antibiotics. The problem has not stimulated research into how to strengthen the immune system. Here is a 1992 editorial in Science: “Mechanisms such as antibiotic control programs, better hygiene [= more handwashing], and synthesis of agents with improved antimicrobial activity need to be adopted in order to limit bacterial resistance.” Nothing about improving immune function. A 2012 World Health Organization report about the problem does not contain the word immune.

2. The idiocy of tonsillectomies. Forty years after researchers figured out that tonsils are part of the immune system, tonsillectomies remain common. Removing tonsils because of too many infections makes as much sense as removing part of the brain because of memory loss. I have never encountered a doctor who appears to understand this.

3. Epidemiologists have yet to systematically study what makes the immune system more or less powerful. For example, this epidemiology textbook does not contain the word immune. Nor does this review of 25 epidemiology textbooks.

4. A respected professor of pharmacology at the University College London named David Colquhoun left the following comment on this blog: “Talking of made up theories, the corniest of all has to be “stimulating the immune system”. There is [not], and never has been, any evidence that it happens — it is the eternal mantra of every quack who is trying to sell you their own brand of implausible therapy.” Here is an example of the evidence he says doesn’t exist. Professor Colquhoun is a Fellow of the Royal Society.

5. I know very little about the immune system. I barely know what a T cell is. My job (psychology professor) has nothing to do with it. Yet I have come up with three ideas related to it: 1. Tonsillectomies are idiotic. 2. We need regular intake of microbes to be healthy — in part to stimulate the immune system. 3. We need exposure in small amounts to the germs around us for our immune systems to best protect us. (So it’s not obvious that outside of hospitals more handwashing is a good thing.) Only because these ideas are obvious (#1 and #3) or semi-obvious (#2) was someone as ignorant as me able to think of them. That one ignorant outsider thought of three of these things before the hundreds of thousands of health researchers did suggests how little they think about the immune system.

Someday the people in charge of our health care — or the rest of us, ignoring them — will figure out how to make our immune systems work much better. We will sleep much better, eat much more fermented foods, take enough Vitamin D at the right time of day, and so on. Perhaps we will wash our hands less and kiss more. Antibiotic usage will go way down, selection for resistant microbes will become much less intense, and antibiotic-resistant microbes will become much less common. The problem will disappear.

How Much Vitamin D Should I Take?

A new study of a quarter million Copenhagen residents found that those with Vitamin D blood levels of 40-70 nmol/L [16-28 ng/ml] had the lowest death rate. People with lower and higher amounts had higher death rates, in other words. The death rate versus blood level function has a reverse-J shape, i.e., too little is worse than too much. About 1% of the sample had levels above 140 nmol/L [56 ng/ml], for practical purposes a “high” level.

Because Vitamin D3 seems to have a big time-of-day-dependent effect on sleep (Vitamin D in the morning improves sleep, Vitamin D in the evening makes sleep worse) it is plausible that people with high Vitamin D levels were more likely to take it in the evening than those with moderate levels and this is why they had higher mortality. Likewise, it is plausible that those with moderate levels were more likely to take Vitamin D in the morning than those with low levels and better sleep explains the lower mortality. Although epidemiologists adjust for smoking in studies like this, they don’t yet adjust for sleep quality. It is also plausible that people who were more sick took more Vitamin D — hoping it would improve their health.

I think I have a better way to decide how much Vitamin D3 to take: choose the minimum amount that produces the best sleep. Sleep is so strongly connected with health that I wouldn’t want to choose worse sleep over better sleep simply because of epidemiology. At the same time that I greatly improved my sleep, I stopped getting easy-to-notice colds. Apparently my immune system was doing a better job of fighting them off.

There is evidence that Vitamin D improves immune function independently of its effect on sleep. A 2009 survey found that “those with less than 10 nanograms of vitamin D per milliliter [25 nmol/L] of blood, considered low, were nearly 40 percent more likely to have had a respiratory infection [over what period of time?] than those with vitamin D levels of 30 ng/ml [75 nmol/L] or higher.”

So those three studies (epidemiology, lab, epidemiology) taken together make a good case that my Vitamin D levels should be at least 25 ng/ml. I will have my Vitamin D level measured soon and it will be interesting to see how much an approach based purely on self-measurement (find the minimum amount of Vitamin D that optimizes sleep) agrees with this.

Thanks to Chase Saunders.

More. In an earlier version of this post I confused ng/ml with nmol/L.

Academic Politics, Alan Turing and Stanford

This series of posts about a proposed Alan Turing conference at Stanford left me wondering about the best academic novels I had read. Pnin is good, but not very academic. Gone by Renata Adler is fantastic but about office politics. I didn’t like Changing Places nor Lucky Jim. I doubt a novel could be better than this:

A couple of days later we received a note from Lester Earnest to say he was withdrawing from the committee. Since Les was underwriting the event this was a blow; we had lost our funding.

I wrote to Les asking him what had happened, knowing that the exchange with [Jennifer] Widom [chair of the Stanford CS department] over the December holiday was surely sufficient to deter and depress anyone.

A few hours later Ed Feigenbaum wrote to the committee saying that he had not spoken to Les but that he would withdraw from the committee himself. This puzzled both me and Les because Les had just told me that Ed that had talked him out of supporting the conference.

Is there a blog about academic politics?

How I Will Teach Next Semester: Human Evolution and College Teaching

I have wondered for a long time how to apply my ideas about human evolution to teaching. My theory of human evolution says that specialization and trading are central to human evolution and includes a mechanism that increases diversity of expertise. The more diverse the expertise of you and your trading partners, the more you gain from trading. If I make knives and you make knives, we will gain less from trading than if I make knives and you make baskets.

I also discovered — independently — that the more choice I gave my Berkeley students (junior and senior psychology majors) about what to learn, the more they learned. It was as if they had an internal drive to learn all sorts of different things and the more I allowed that motivation to push and guide them, the more they learned. To see big effects it wasn’t enough to merely give them a wide choice of term paper topics (as many college teachers do). I pushed them out into the “real” (off-campus) world (they couldn’t do a library project) and said learn whatever you want. In this situation they learned an enormous amount. The connection with my theory of evolution was obvious: something inside of them was pushing them to be diverse in what they learned. What they learn = what they will become expert in. What they become expert in = what they will have to trade.

The more I allowed the underlying diversity of my students to be expressed, the more they learned. Yet almost all college classes treat all of the students in the class the same: same material, same assignments, same tests. The diversity of the students — especially the ways they differ from the professor — is a nuisance. So my theory suggests that standard college teaching is greatly at odds with human nature. It assumes one size fits all when that could hardly be more wrong. It should be possible to greatly increase how much is learned by doing a better job of recognizing human nature. My experience so far supports this prediction.

Recently I thought of a new way to deal with diversity among my students. Next semester I will try it. One of the courses I am teaching (at Tsinghua University) is Frontiers of Psychology, with about 25 students. It’s required of freshman psychology majors. Here’s what I’ll do. For the first four or five class periods (one class per week), I’ll cover a wide range of psychological topics, ideas, and methods. There will be reading assignments (e.g., choose one paper out of 30 and do a class presentation) but no grading. Then every student will draw up a list of “learning goals” for the rest of the semester. The goals can be whatever they want (related to psychology). They can read a book, read some articles, collect some data, give a talk to a high school class, whatever. Each goal will have a deadline. The assessment will be binary: goal completed/not completed. Their final grade will depend on how many goals they completed. The goals will be ordered. The further down their list they get, the higher their grade, with each level of completion assigned a grade at the beginning. They will make class presentations throughout the semester about their progress: what they are doing, what they have learned.

For the students, the benefits (compared to conventional teaching) are that (a) they get to learn exactly what they want yet (b) the grading criteria are very clear and (c) they are still motivated to work. For me, the benefits are that it should be a lot easier to judge if a goal has been completed than to grade homework essays, which is what I’ve done recently. Nor will I have to worry about what happens in class each week.

Any comments?