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Medical contrarianism isn’t always right

A few years ago, for a stretch lasting a year or two, I boycotted LewRockwell.com because their all-too-frequent Creationist columns were embarrassing to the libertarian movement and I didn’t want to be associated with those types of people, nor reward the publication of such hokum with additional page hits. It wasn’t a complete boycott, because I did visit once in a while, and I continued to frequent Mises.org, but the point is that just because the State-funded and State-supporting majority take a certain position, it doesn’t make it wrong.

I am much more forgiving of what you might call medical revisionism because so much about mammalian genetics, biochemistry, and physiology is unknown—especially for humans because we can’t do the same types of studies on humans that we can do in rodents. However, some contrarianism just goes too far. See, for example, Dr. Ernest Curtis’s column at LRC today, The Healthcare Delusion. The relevant passages from his August 12 column:

…exercising and maintaining physical fitness certainly provide a sense of well-being for most people. There is no question that physical fitness provides one with a feeling of more energy and the ability to get around with less fatigue, sluggishness, etc. But there is not a scintilla of scientific evidence that exercise or fitness prevents disease or prolongs life despite the never-ending exhortations to the contrary.

Diet is an even greater source of misunderstanding and misinformation. The attempt to link diet to health and disease has a long and rich history. The only thing lacking is any scientifically credible evidence that the two are related. Most of the so-called “evidence” that is cited comes out of a pseudoscience known as epidemiology.*

The phrase “Extraordinary claims require extraordinary evidence” comes to mind. I’m sure Dr. Curtis would claim that, if not for bogus studies based on fraudulent or manipulated statistics, the claim that diet and exercise have nothing to do with health, disease, or longevity wouldn’t be the least bit extraordinary. However, as things stand in the scientific and medical communities, it is extraordinary, and I don’t believe it.

As a bit of layman’s evidence or simple common sense, though, consider what he’s saying: two of the most basic, essential elements of our being—our physical activity level and the food we eat—have absolutely nothing to do with how healthy, sick, or long-lived we are. He’s not saying, Well, you can exercise a lot and extend your lifespan a little, but genetics and luck are going to kill you around a certain age no matter what you do. He’s not saying, Exercising your muscles and getting your heart in good shape will only improve the last few years of your life a little and you’ll probably die of cancer or Alzheimer’s anyhow. He’s saying: Yeah, eating bon bons, drinking Kool-Aid and beer all day, and sitting on your butt might make you feel sluggish, but it isn’t actually bad for you.

I’ll give you one piece of concrete evidence against him: greater muscle use protects against osteoporosis, especially in women. Osteoporosis is a disease, which all women are at risk for because of menopause, and which some women are more predisposed to than others, and which exercise forestalls and mitigates. This is because of the all-too-obvious and commonsensical notion that if you use your muscles and the bones they’re attached to, they will be stronger.

There are many who, like myself, think there is much wisdom to be found in considering where man came from—our roots in the ice age and jungle, our more “natural” state—to understand what ails us in the modern world. This applies more to medicine and physiology than anything. For instance, maybe a lot of foot, ankle, and knee injuries are due to fancy running shoes that coddle our feet too much. Or that dirty city air contributes to asthma more than rural air. So to me it’s obvious that humans evolved to labor and to consume a diet substantially different from a typical Western diet. Physical activity—hunting, building, traveling, escaping from predators—is part of our “natural” way of life. Letting go of that is bad for you. Eating animals, fruits, and vegetables is our “natural” diet. Replacing them with high-fructose corn syrup and too calorie-dense foods (with the main culprit probably being carbohydrates) is bad for you.

How can two such integral parts of our nature and our evolution bear no relation to our physical health? True, there are other primal factors from our past that are clearly detrimental to human health and cultural progress. A philosophy of Might Makes Right, racism, sexism, and a lack of dentistry, for example. Those aren’t the same as exercise and diet, fortunately.

The more specific parts of his column, that I felt more qualified to comment on, were his claims about obesity and type 2 diabetes, which I have studied for the last five years. He wrote:

There seems to be a lot of hysteria about an “obesity epidemic” which is ruining our national health (whatever that is). But the critics have yet to confront the fact that life expectancy continues to rise despite this horrible affliction. Actuarial statistics show that moderate obesity (as currently defined) has no significant effect on life expectancy. It is true that the morbidly obese have significant health problems but these are most often due to mechanical factors such as extreme obesity that limits the ability to breathe normally.

There have been many attempts to link obesity with diabetes but this association is tenuous at best. There are literally millions of people who are obese but show no evidence of diabetes. Conversely, there are lots of thin and physically fit individuals who are severe diabetics. It is true that some people may show a diabetic-like pattern of glucose intolerance when they gain weight and revert to normal when they shed some pounds. These individuals may have a marginal genetic tendency towards diabetes where the anti-insulin effects of excess body fat may reveal a pattern of glucose intolerance. But they rarely suffer the severity or the secondary problems seen in the truly diabetic.

The idea that one can eat his way to diabetes is sheer nonsense. Some of the confusion arises because of fundamental misunderstanding about the disease process in diabetes. Because diabetics have either a relative or absolute lack of insulin, their blood sugar (glucose) level may rise quite high if they ingest a glucose load. In order to avoid the secondary metabolic effects of a high blood sugar (or, more accurately, a relative deficiency of intracellular sugar), diabetics need to pay close attention to the amount of carbohydrate in their diet. But the glucose level in the blood is really only a marker for the disease. The sugar itself does no harm other than dehydrating the individual due to the osmotic effect. There are many other effects which produce the typical diabetic syndrome (accelerated atherosclerosis, kidney failure, blindness, etc.). It has been shown that even near perfect control of the blood glucose level does little to prevent these complications in the truly diabetic. The underlying cause seems to be genetic and affects the insulin production and perhaps other factors as well. But one can eat all the sugar one wishes and never develop diabetes if the underlying genetic cause is not present.

So what is one to do in order to maintain health and well-being? It would be nice if we could do so by following a “healthy” lifestyle or diet. But, unfortunately, that is not consistent with biological reality. Most likely good health is a combination of genetics and pure dumb luck.

In response, I sent him the following email:

Dear Dr. Curtis,

I don’t know much about cardiovascular disease or your claims about the effects of cholesterol on it, nor do I want to challenge your statement that moderate obesity doesn’t affect health or life expectancy, but your insinuation that behavior and lifestyle have little to no effect on their incidence is wrong. One of the main theses of your LRC article was that behavioral factors (diet, exercise) have no effect on health and disease, and that genetic and stochastic factors are entirely to blame. Perhaps it would be fair to sum up this point with your sentence, “Most likely good health is a combination of genetics and pure dumb luck.”

Unfortunately, it is not possible to explain the dramatic increase in the incidence of obesity and type 2 diabetes by genetics alone (and certainly not luck). If your claim had any truth, then it would require a huge change in a small subset of allele frequencies in nearly every population across the world in about two generations. Such dramatic and peculiar evolution is absurd and impossible. Therefore, if genes aren’t the cause, external factors are. More people are obese and diabetic, it’s happening at younger ages, our diets have more fat, processed sugar, and calories than before, and we exercise less, especially in the West. But diet and behavior have nothing to do with either of those conditions?…

This is especially unlikely given the fact that the United States, the most obese and diabetic nation in the world, is also the most genetically heterogeneous nation in the world, and the fact that obesity, diabetes, and other non-infectious disorders have become more common in every ethnic group here. It isn’t just due to longer lives or genetics or bad luck or our State-infected medical system (as bad as that is).

I was also interested in your paragraph about the tenuous link between obesity and diabetes. This is certainly true. Many of my colleagues across the world have been searching for a causal link between obesity and diabetes and have found nothing very conclusive. The leading theory is that ectopic fatty acids/triglycerides, mainly in muscle, beta-cells, and liver, impair insulin sensitivity or insulin secretion in some way. As anyone familiar with the effects of TZD’s knows, it is not obesity per se that is bad for you, it’s the ectopic fat. Adipose tissue is good for you; the more fat it stores, the less spillover there will be to the blood and insulin-sensitive organs. There are a few mechanistic hypotheses for how ectopic fatty acids contribute to insulin resistance, and maybe some of them hold water.

This is another way diet comes into play. Our genetic capacity to expand our adipose tissue has not changed in 50 years, and likely not in 50 centuries. Our diets and our lifestyles have. We don’t have excess fat in our livers and muscles because of genetics and pure dumb luck, we have it there because we eat unbalanced diets, consume too many calories, and exercise too little.

When you wrote, “But one can eat all the sugar one wishes and never develop diabetes if the underlying genetic cause is not present,” you left out the inverse statement: But if the underlying genetic cause is present, gorging yourself with sugar will accelerate and worsen the diabetes when it does develop. To deny this seems to me to go far beyond healthy skepticism and well into the delusion you claim to rail against.

Since I don’t read very many clinical articles or treat patients, I’m not ready to argue your point that the increase in obesity and type 2 diabetes is nothing to get worked up about since they won’t kill you, at least not at a younger age than our ancestors died at. But to claim diet and behavior have exactly nothing to do with the onset of obesity or diabetes (or, I’d wager, cardiovascular disease) is irresponsible and nonsensical. It strikes me as akin to claiming that a person predisposed to alcoholism will become an alcoholic whether he ever consumes a drop of alcohol or not. When you peddle unsupported and nonsensical anti-establishment medical claims, it discredits your other contrarian arguments that do hold water and that could appeal to libertarians and non-libertarians alike. It also contributes to the (false) impression of libertarians as contrarian, revisionist nutjobs; we are contrarian, revisionist, smart, normal people. Maybe you can address these and other objections in a future column.

I would have been harsher or more detailed, but I’m working on being a little more professional and magnanimous. Besides, I think he’s right about a lot of other things, just not the parts I quoted. I haven’t heard back from him yet.

Posted in Medicine, Science