Seth's Blog

Not as fast as we used to. A friend of mine, who went to college at MIT around 1980, had a classmate who was the son of an undertaker. His dad had told him that when he (the dad) had entered the business, you had to work fast. Bodies would start to smell quickly. But now — around 1980 — that was no longer necessary. You could wait a lot longer before they smelled bad.

Which I take to mean that around 1980 the average old person, where this classmate came from, had a lot less bacteria in their body than around 1960. All that concern about “the safety of the food supply” — preservatives, yes, but also sterilization, freezing, sell-by dates, food handling rules, food safety officers, and microwave food — seems to have had an effect. From 1960 to 1980 there was a big shift from homemade food to factory-made and restaurant-made food. The uniformity of the new food caused the obesity epidemic, I believe; its sterility  caused a great increase in allergies and asthma, not to mention a bunch of other disorders.
Speaking of sell-by dates, at a Japanese grocery store recently I wanted to buy some Yakult. At check-out, it was pointed out to me that it was one day past its sell-by date. Half price. I bought two.

Freestone Fermentation Festival.

If you are going and live near Berkeley, could I get a ride?

Thanks to Mariah Isley.

A 2005 study compared workers who did and did not consume a daily straw of probiotic liquid. During the 3-month study, workers who got the probiotics were sick half as often as those who didn’t. Here are details:

262 employees at TetraPak in Sweden (day-workers and three-shift-workers) that were healthy at study start were randomised in a double-blind fashion to receive either a daily dose of 100,000,000 Colony Forming Units of L. reuteri or placebo for 80 days. The study products were administered with a drinking straw. 181 subjects complied with the study protocol, 94 were randomised to receive L. reuteri and 87 received placebo. In the placebo group 26.4% reported sick-leave for the defined causes during the study as compared with 10.6% in the L. reuteri group (p < 0.01). The frequency of sick-days was 0.9% in the placebo group and 0.4% in the L. reuteri group (p < 0.01). Among the 53 shift-workers, 33% in the placebo group reported sick during the study period as compared with none in the L. reuteri group(p < 0.005).

The paper gives no reason to think the probiotic dose was optimal. (How the dose was chosen isn’t explained.) A larger dose might have had a bigger effect.

When science writers tell about the “miracle” of antibiotics, they tell stories like this one, from The Probiotics Revolution (2007) by Gary Huffnagle with Sarah Wernick:

When my daughter was five, she pricked her left hand on a rosebud thorn in our garden. . . . The next day she ran a fever. . . . Doctors diagnosed an acute bacterial infection. Half a century ago, a child might have died from such an infection. But my daughter received antibiotics. After a day of intravenous treatment, she was better. . . . Antibiotics are true miracle drugs.

What goes unnoticed in these “miracle” accounts is the possibility that the person got so sick because their immune system wasn’t working well. (It wasn’t working well, I propose, because the infected person didn’t get enough bacteria in their food.) A child gets sick from an ordinary plant scratch? That child’s immune system has a lot of room for improvement. Huffnagle and Werrick say nothing about this.

Dr. Huffnagle is a professor of internal medicine, microbiology, and immunology at the University of Michigan. If the child of such a parent — well-off, well-educated, health-conscious, specializing in immunology — has a weak immune system, and the parent doesn’t realize this is possible, there is enormous room for improvement.

The Probiotics Revolution is 90% filler but the 10% substance makes it worth skimming.

Noticing that flaxseed oil improved my balance led me to measure its effects on other tests of brain function. It also made me wonder what else in my life affected how well my brain works. Eventually I measured the mental effects of flaxseed oil with four tests, but each had problems:

1. Balance. Time-consuming (15 minutes for one daily test), not portable.
2. Memory search.  Anticipation errors, speed-accuracy tradeoff.
3. Arithmetic. Speed-accuracy tradeoff.
4. Digit span. Insensitive.

“Speed-accuracy tradeoff” means it was easy to go faster and make more errors. It wasn’t easy to keep the error rate constant. If I got faster, there were two possible explanations: (a) brain working better or (b) shift on the speed-accuracy tradeoff function. The balance and digit span tests had other weaknesses. Only the balance test was enjoyable.

I’m still doing the arithmetic test, which has been highly informative. However, I want to regularly do at least two tests to provide a check on each other and to allow test comparison (which is more sensitive?). I tried a test that involved typing random strings of letters several times but as I got faster I started to make many mistakes.

I have recently started doing a test that consists of one-fingered typing of a five-letter string. There are 30 possible five-letter strings. Each trial I see one of them and type it as fast as possible. 15 trials = one test. Takes three minutes.

I am doing one-finger rather than regular typing because I hope one-finger typing will be more accurate, very close to 100%. With the error rate always near zero, I won’t have to worry about speed-accuracy tradeoff. Another reason is the need for skilled movement and hand-eye coordination. Doing this sort of task can be enjoyable. One-finger typing (unlike regular typing) is skilled movement with hand-eye coordination; maybe it will be fun.

I restricted the number of possible letter strings to 30 to make learning easier. Yet 30 is too large to cause the anticipation errors I might make if there were only a few strings.

Here are early results.

So far so good. Accuracy is high. On any trial, it isn’t easy to go faster, so speed-accuracy tradeoff is less of a problem. Even better, it’s vaguely enjoyable. Doing the task is a little like having a cup of tea. A pleasant break. There’s no need to do the test four times/day; I just want to.

From BBC News:

A specialist light treatment for psoriasis is just as effective and safe when given at home as in hospital, say Dutch researchers. Phototherapy using UVB light is rarely used in the UK because of limited availability and the number of hospital visits required. But a study of 200 patients found the same results with home treatment. . . .

One reason that the treatment is usually done in hospital is because most dermatologists believe that home phototherapy is inferior and that it carries more risks.In the latest study, patients with psoriasis from 14 hospital dermatology departments were randomly assigned to receive either home UVB phototherapy or hospital-based treatment. Home treatment was equivalent to hospital therapy both in terms of safety and the effectiveness of clearing the condition. And those treated at home reported a significantly lower burden of treatment and were more satisfied.

There was a time when blood-glucose testing (for diabetes) was only done in laboratories, with blood drawn in doctors’ offices or hospitals.