Tuesday, April 29, 2008

Starve a Fever?

You've all heard the old adage, "Feed a cold, starve a fever." Many websites claim that this adage is just a myth (see here or here).

I fortuitously stumbled across this study, the purpose of which was to show that eating simple carbs (such as sugar) brings down the body's ability to scavenge for harmful bacteria (namely, Staphyloccus epidermidis, a very common bacteria that causes fevers or even fatal meningitis).

Notice the last sentence of the abstract, which shows that a 36- or 60-hour fast also improved the body's ability to fight off staph bacteria:
American Journal of Clinical Nutrition, Vol 26, 1180-1184, Copyright © 1973

Role of sugars in human neutrophilic phagocytosis

Albert Sanchez, J. L. Reeser, H. S. Lau, P. Y. Yahiku, R. E. Willard, P. J. McMillan, S. Y. Cho, A. R. Magie, and U. D. Register

1 From the Departments of Nutrition, Biostatistics, and Environmental Health in the School of Health, and the Department of Microbiology, Pathology, and Anatomy in the School of Medicine, Loma Linda University, Loma Linda, California 92354

This study was designed to test a) whether carbohydrates other than glucose decreased the phagocytic capacity of neutrophils in normal human subjects, b) the duration of this effect, and c) the effect of fasting on neutrophilic phagocytosis. Venous blood was drawn from the arm after an overnight fast and at 0.5, 1, 2, 3, or 5 hr postprandial and this was incubated with a suspension of Staphylococcus epidermidis. The phagocytic index (mean number of bacteria viewed within each neutrophil) was determined by microscopic examination of slides prepared with Wright's stain. Oral 100-g portions of carbohydrate from glucose, fructose, sucrose, honey, or orange juice all significantly decreased the capacity of neutrophils to engulf bacteria as measured by the slide technique. Starch ingestion did not have this effect. The decrease in phagocytic index was rapid following the ingestion of simple carbohydrates. The greatest effects occurred between 1 and 2 hr postprandial, but the values were still significantly below the fasting control values 5 hr after feeding (P < 0.001). The decreased phagocytic index was not significantly associated with the number of neutrophils. These data suggest that the function and not the number of phagocytes was altered by ingestion of sugars. This implicates glucose and other simple carbohydrates in the control of phagocytosis and shows that the effects last for at least 5 hr. On the other hand, a fast of 36 or 60 hr significantly increased (P < 0.001) the phagocytic index.
More recently, there was a small study that tended to confirm "feed a cold, starve a fever."
The maxim "feed a cold, starve a fever" may be right after all, researchers have discovered.

Until now, most doctors and nutritionists have rejected the idea as a myth. But Dutch scientists have found that eating a meal boosts the type of immune response that destroys the viruses responsible for colds, while fasting stimulates the response that tackles the bacterial infections responsible for most fevers.

"To our knowledge, this is the first time that such a direct effect has been demonstrated," says Gijs van den Brink of the Academic Medical Center in Amsterdam.

Rev. Wright on Black Education

I've said it before, but it is a mystery to me that some people consider it progressive or enlightened to suggest that black people are not good at being "logical and analytical."

Friday, April 25, 2008

Elevator Stories

So everyone is linking to this long and fascinating story about elevators. I liked the passage on elevator etiquette:
Passengers seem to know instinctively how to arrange themselves in an elevator. Two strangers will gravitate to the back corners, a third will stand by the door, at an isosceles remove, until a fourth comes in, at which point passengers three and four will spread toward the front corners, making room, in the center, for a fifth, and so on, like the dots on a die. With each additional passenger, the bodies shift, slotting into the open spaces. The goal, of course, is to maintain (but not too conspicuously) maximum distance and to counteract unwanted intimacies—a code familiar (to half the population) from the urinal bank and (to them and all the rest) from the subway. One should face front. Look up, down, or, if you must, straight ahead. Mirrors compound the unease. Generally, no one should speak a word to anyone else in an elevator. Most people make allowances for the continuation of generic small talk already under way, or, in residential buildings, for neighborly amenities.
Reminds me of two things:

1. The great Candid Camera stunt where people stood facing backwards on an elevator (and others not in on the stunt turned to face backwards too).

2. This marvelous anecdote about Alfred Hitchcock:
My own favorite memory of Hitchcock comes from an incident at the St. Regis Hotel in New York in 1964. After some frozen daiquiris had left me a bit tipsy and Hitch quite red-faced and cheerful, we got on the elevator at the 25th floor and rode in silence to the 19th, where, when three people dressed for the evening entered, he suddenly turned to me and said, ''Well, it was quite shocking, I must say there was blood everywhere!'' I was confused, thinking that because of the daiquiris I'd missed something, but he just went right on: ''There was a stream of blood coming from his ear and another from his mouth.'' Of course, everyone in the elevator had recognized him but no one looked over. Two more people from the 19th floor entered as he continued: ''Of course, there was a huge pool of blood on the floor and his clothes were splattered with it. Oh! It was a horrible mess. Well, you can imagine . . . '' It felt as if no one in the elevator, including me, was breathing. He now glanced at me, I nodded dumbly, and he resumed: ''Blood all around! Well, I looked at the poor fellow and I said, 'Good God, man, what's happened to you?'' And then, just as the elevator doors opened onto the lobby, Hitchcock said, ''And do you know what he told me?'' and paused. With reluctance, the passengers now all moved out of the elevator and looked anxiously at the director as we passed them in silence. After a few foggy moments, I asked, ''So what did he say?'' And Hitch smiled beatifically and answered, ''Oh, nothing -- that's just my elevator story.''

Thursday, April 24, 2008

Edward Lorenz

I just noticed that Edward Lorenz died. I've long admired his contributions to chaos theory. Which brings something to mind: if I had to make a list of the top three scientific principles most likely to be invoked in inapt situations by non-scientists who don't really know what they're talking about (and I'm probably guilty of this on occasion), the list would be: 1) relativity; 2) Heisenberg uncertainty principle; and 3) chaos theory.

Tuesday, April 22, 2008

Richard Dawkins

A recent column by Richard Dawkins, presenting what purport to be arguments against the existence of God:
Entities capable of designing anything, whether they be human engineers or interstellar aliens, must be complex -- and therefore, statistically improbable.
But says who? How does Dawkins purport to know that any entity that could be deemed "God" is both "complex" and "statistically improbable"? Elsewhere, Dawkins has written derisively of the "argument from personal incredulity," i.e., the argument that because one is personally incredulous that evolution could have done this or that, therefore evolution didn't do it. Fair enough. But here, Dawkins is offering his own argument from personal incredulity here -- he says that God is "statistically improbable," but given that the statistics cannot be measured here, Dawkins is saying nothing other than that he is personally incredulous when he thinks about the possibility of God. I don't think this proves anything.

Later Dawkins amplifies:
Theologians attempt two (mutually incompatible and pathetically inadequate) answers to this unanswerable point. Some say their God is not complex but simple. This obviously won't wash. No simple god could design bacterial flagellar motors or universes, let alone forgive sins or impregnate virgins.
Again, says who? Dawkins seems to think that he's stumbled on a definitional principle here: Anything complex must have arisen from something else that is of equal or greater complexity. But as can be seen from the world of fractals, such a principle is certainly not universal: apparent complexity can arise from simple equations. (If Stephen Wolfram is right, then more than just fractals can be generated from simplicity.) I wonder if Dawkins has attempted to demonstrate this principle elsewhere.

I understand where Dawkins is coming from -- he views it as stealing a base for theologians just to assert that "God" is "simple" yet able to create "complexity." The problem, though, is that Dawkins has no more substantiation for his supposed disproof, which is just the bald assertion that "God" cannot be "simple."
Presumably recognizing the justice of that, other theologians go to the opposite extreme. They admit that their god is complex but assert that he had no beginning: He was always there and always complex. But if you are going to resort to that facile cop-out, you might as well say flagellar motors were always there.
What is this supposed to mean? We already know for sure that life was not "always there," and apart from a few implausible theories, the universe itself was not "always there" either. So the real question is whether the universe somehow sprung into being out of nothing, or whether some outside entity had anything to do with it.

I've always found this argumentative move baffling -- if someone accepts that the universe had a beginning and tries to speculate about what (if anything) came before, it's no answer for Dawkins to say (because he doesn't like where the speculation is heading) that we "might as well" pretend the universe always existed. That's not a satisfying answer. (Maybe you don't find "God" a satisfying answer either, but at least it has the virtue of not being such an obvious pretense.)

Monday, April 21, 2008

Jay Greene Blog

My friend Jay Greene -- of the Manhattan Institute and the University of Arkansas's Department of Education Reform -- has a new blog on education issues. Worth checking out.


Sunday, April 20, 2008

Philosophy of Mind Humor

From Eliezer Yudkowsky, here. I like the scene with David Chalmers in a cell.

Friday, April 11, 2008

Tabata Intervals

An update on the Tabata intervals, which I blogged about here.

I sprained my knee a few weeks ago, unfortunately; I'm back to walking comfortably, but running still is painful. So I've been doing the Tabata regime for other exercises that aren't so high-impact (i.e., that don't require you to land with all your weight on one foot).

-- The exercise bike. This is very effective and intense, and can induce such oxygen debt that I have to lie down on the floor after I'm done; I can't even walk right away. So that's about perfect. In fact, the exercise bike is what Tabata himself used in his studies.

-- Tabata squats. I can get 20-22 squats per every 20 second interval. This is very intense on the thigh muscles, although the oxygen debt is not quite as severe. I've seen some of the CrossFit folks doing Tabata squats while making everyone rest by holding a squat position, rather than actual rest:

I very much disagree with this. It would increase the intensity on the thigh muscles, but as you can see from that video, most of the people are not able to do the actual squats at anything like a real sprint pace. But the whole point of Tabata intervals is to sprint all-out so that you exhaust both your aerobic and anaerobic capacities. If you get rid of rest periods and make the exercise even more intense on your muscles than it already is, then you'll end up slowing down so much that you simply won't be able hit your anaerobic peak. So it seems to me.

-- Burpees. Here's what that exercise looks like:

You start from a squatting position; kick back to a push-up position; kick back to the squatting position; and from there jump into the air as high as you can. Then repeat.

A lot of people do an actual push-up in there. I don't agree with this, at least not for the Tabata intervals. For me, a push-up slows things down, and gives my legs a momentary break from the all-out-sprint effect. Again, the point of Tabata intervals isn't to give all of your muscles a good work-out in one exercise; it's to push the pace to an all-out sprint and exhaust the anaerobic capacity.

The first time I tried Tabata burpees, I could only do 4 sets before staggering away gasping for breath. Now I'm up to 8 sets, but it's still very intense and keeps me out of breath for the next 10 or 15 minutes.

-- Deadlifts. I tried Tabata deadlifts with a 70-pound barbell. The entire back of my body was sore for days, except for the calves. That was all good, but I don't know that I'll ever try to do deadlifts in sprint-fashion again; it seems like it would be too easy to get sloppy and strain your back.

Thursday, April 10, 2008

Deadly Eggs

If you eat six eggs a week, you're fine; but seven or more eggs per week increases your risk of death by 23% (not 24% or 22%, mind you). So says a new study.

But those readers who scroll down to the very end of the article find this:
Men who ate the most eggs also were older, fatter, ate more vegetables but less breakfast cereal, and were more likely to drink alcohol, smoke and less likely to exercise -- all factors that can affect the risk of heart attack and death.
I haven't read the whole study, but I'd imagine that those latter factors would affect the results.

Saturday, April 05, 2008

Overuse of Medicine

Via Newmark's Door, here's a NY Times story on some of the incentives that lead to the overuse of medicine:
I recently took care of a 50-year-old man who had been admitted to the hospital short of breath. During his monthlong stay he was seen by a hematologist, an endocrinologist, a kidney specialist, a podiatrist, two cardiologists, a cardiac electrophysiologist, an infectious-diseases specialist, a pulmonologist, an ear-nose-throat specialist, a urologist, a gastroenterologist, a neurologist, a nutritionist, a general surgeon, a thoracic surgeon and a pain specialist.

He underwent 12 procedures, including cardiac catheterization, a pacemaker implant and a bone-marrow biopsy (to work-up chronic anemia).

Despite this wearying schedule, he maintained an upbeat manner, walking the corridors daily with assistance to chat with nurses and physician assistants. When he was discharged, follow-up visits were scheduled for him with seven specialists.

This man’s case, in which expert consultations sprouted with little rhyme, reason or coordination, reinforced a lesson I have learned many times since entering practice: In our health care system, where doctors are paid piecework for their services, if you have a slew of physicians and a willing patient, almost any sort of terrible excess can occur.

* * *

Overutilization is driven by many factors — “defensive” medicine by doctors trying to avoid lawsuits; patients’ demands; a pervading belief among doctors and patients that newer, more expensive technology is better.

The most important factor, however, may be the perverse financial incentives of our current system.

* * *

Not long ago, I visited a friend — a cardiologist in his late 30s — at his office on Long Island to ask him about imaging in private practices.

“When I started in practice, I wanted to do the right thing,” he told me matter-of-factly. “A young woman would come in with palpitations. I’d tell her she was fine. But then I realized that she’d just go down the street to another physician and he’d order all the tests anyway: echocardiogram, stress test, Holter monitor — stuff she didn’t really need. Then she’d go around and tell her friends what a great doctor — a thorough doctor — the other cardiologist was.

“I tried to practice ethical medicine, but it didn’t help. It didn’t pay, both from a financial and a reputation standpoint.”

His nuclear imaging camera was in an adjoining “procedure” room. He broke down the monthly costs for me: camera lease, $4,500; treadmill lease, $400; office space, $1,000; technician fee, $1,800; nurse fee, $1,000; and miscellaneous expenses of $200.

“Now say I get on average $850 per nuclear stress test,” he said. “Then I have to do at least 10 stress tests a month just to cover the costs, no profit going into my pocket.”

“So,” I said, “there’s pressure on you to do more than 10 stress tests a month, whether your patients need it or not.”

He shrugged and said, “That is what I have to do to break even.”

Tuesday, April 01, 2008

No More Rickrolling

So there's this phenomenon called "rickrolling," which consists of tricking someone into clicking on a link that really goes to Rick Astley's classic video for "Never Gonna Give you Up." Now, I have a lot of respect for Rick Astley; I remember when his album was legitimately cool, not just in an ironic way. Rick's vocals were so smooth. And that "I'm shaking invisible maracas" dance move was way ahead of its time -- so far ahead that its time may never come. Plus, what a bartender that was. Check out his "bounce the fence" move at 2:07.

So I think that it's time for everyone to abandon rickrolling. It's too cliched, and plus Rick Astley was just too good to mock in that way.

Instead, people should "wham" each other, that is, trick people into clicking on Wham's classic video for "Wake Me Up Before You Go Go." Reasons for this include:

1) George Michael's bouncy hair.

2) His awesome dance moves (the leap at 28-29 seconds will never be equalled, nor will the dance move at 2:10);

3) Andrew Ridgeley. Need I say more? (I thought he never actually did anything in Wham, but it turns out that he could play the electric guitar without a cord.)

Overcoming Bias

Another post by me.