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It’s a part of my paleo fantasy, it’s a part of my paleo dream

There are many fallacies that undergird alternative medicine, which evolved into “complementary and alternative medicine” (CAM), and for which the preferred term among its advocates is now “integrative medicine,” meant to imply the “best of both worlds.” If I had to pick one fallacy that rules above all among proponents of CAM/IM, it would have to be either the naturalistic fallacy (i.e., that if it’s natural—whatever that means—it must be better) or the fallacy of antiquity (i.e., that if it’s really old, it must be better). Of course, the two fallacies are not unrelated. In the minds of CAM proponents, old is more likely to have been based on nature, and the naturalistic fallacy often correlates with the fallacy of antiquity. Basically, it’s a rejection of modernity, and from it flow the interest in herbalism, various religious practices rebranded as treatments (thousands of years ago, medicine was religion and religion was medicine—the two were more or less one and physicians were often priests as well), and the all-consuming fear of “toxins,” in which it is thought that the products of modernity are poisoning us.

Yes, there is a definite belief underlying much of CAM that technology and pharmaceuticals are automatically bad and that “natural” must be better. Flowing from that belief is the belief that people were happier and much healthier in the preindustrial, preagricultural past, that cardiovascular disease was rare or nonexistent, and that cancer was seldom heard of. Of course, it’s hard not to note that cancer and heart disease are primarily diseases of aging, and life expectancy was so much lower back in the day that a much smaller percentage of the population lived to advanced ages than is the case today. Even so, an implicit assumption among many CAM advocates is that cardiovascular disease is largely a disease of modern lifestyle and diet and that, if modern humans could somehow mimic preindustrial or, according to some, even preagricultural, lifestyles, that cardiovascular disease could be avoided. Not infrequently, evolutionary and genomic arguments are invoked, claiming that the estimated 10,000 years since the dawn of human agriculture is not a sufficiently long period of time for us to have evolved to handle diets rich in grains and meats and that we are “genetically wired” to exist on a diet like those of our paleolithic hunter-gatherer ancestors. For instance, in 2004, James H. O’Keefe Jr, MD and Loren Cordain, PhD wrote an article in the Mayo Proceedings entitled Cardiovascular Disease Resulting From a Diet and Lifestyle at Odds With Our Paleolithic Genome: How to Become a 21st-Century Hunter-Gatherer that asserted in essence, just that. Over the last decade, Cordain has become the most prominent promoter of the so-called “Paleo diet,” having written The Paleo Diet: Lose Weight and Get Healthy by Eating the Foods You Were Designed to Eat and multiple other books advocating a paleolithic-mimetic diet as the cure for what ails modern humans. Meanwhile, diets thought to reflect what our hunter-gatherer ancestors ate, such as the Paleo Diet consisting largely of animal and fish that can be hunted and fruits and vegetables that can be foraged for in the wild, have been promoted as a near-panacea for the chronic diseases of aging, such as cardiovascular disease and cancer.

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Posted in: Evolution, History, Nutrition

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Gender Differences and Why They Don’t Matter So Much

Several incidents have recently created divisions within the skeptical community.  The latest one was over a casual comment Michael Shermer made in an online talk show. He was asked why the gender split in atheism was not 50/50, “as it should be.” He said he thought it probably was 50/50, and suggested that the perception of unequal numbers might be because attending and speaking at atheist conferences was more of “a guy thing.” They might have asked him to explain what he meant. They didn’t. He didn’t mean to say it was encoded in the male DNA. He was simply recognizing a reality of our society: male/female interests and behavior tend to differ due to all sorts of cultural influences. Among other things, women might find it more difficult to attend meetings because of lower incomes and the need to arrange for babysitters. Watching sports on TV with other guys and beer is a guy thing too, but not because it’s hardwired into the male brain. It’s a guy thing because of customs and attitudes in our society.  And it certainly doesn’t mean women are less capable or that societal influences can’t be overcome.

Nevertheless, Ophelia Benson assumed Shermer meant:

that women are too stupid to do nontheism. Unbelieving in God is thinky work, and women don’t do thinky, because “that’s a guy thing.”

That’s not what he meant. It’s not fair to judge him by one off-the-cuff remark. His record stands for itself: there is not a hint of sexism in his writings and he has always fully acknowledged women’s intelligence and their ability to think critically.

In a rebuttal article, Shermer quoted me:

I think it is unreasonable to expect that equal numbers of men and women will be attracted to every sphere of human endeavor. Science has shown that real differences exist. We should level the playing field and ensure there are no preventable obstacles, then let the chips fall where they may.

PZ Myers called this “a sexist remark.” (more…)

Posted in: Evolution, History

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Epigenetics: It doesn’t mean what quacks think it means

Epigenetics. You keep using that word. I do not think it means what you think it means.

I realize I overuse that little joke, but I can’t help but think that virtually every time I see advocates of so-called “complementary and alternative medicine” (CAM) or, as it’s known more commonly now, “integrative medicine” discussing epigenetics. All you have to do to view mass quantities of misinterpretation of the science of epigenetics is to type the word into the “search” box of a website like Mercola.com or NaturalNews.com, and you’ll be treated to large numbers of articles touting the latest discoveries in epigenetics and using them as “evidence” of “mind over matter” and that you can “reprogram your genes.” It all sounds very “science-y” and impressive, but is it true?

Would that it were that easy!

You might recall that last year I discussed a particularly silly article by Joe Mercola entitled How your thoughts can cause or cure cancer, in which Mercola proclaims that “your mind can create or cure disease.” If you’ve been following the hot fashions and trends in quackery, you’ll know that quacks are very good at leaping on the latest bandwagons of science and twisting them to their own ends. The worst part of this whole process is that sometimes there’s a grain of truth at the heart of what they say, but it’s so completely dressed up in exaggerations and pseudoscience that it’s really, really hard for anyone without a solid grounding in the relevant science to recognize it. Such is the case with how purveyors of “alternative health” like Joe Mercola and Mike Adams have latched on to the concept of epigenetics.
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Posted in: Basic Science, Cancer, Evolution, Neuroscience/Mental Health

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Worms, Germs, and Dirt: What Can They Teach Us About Allergies and Autoimmune Diseases?

Whipworms in the intestine

Whipworms in the intestine. Click to enlarge.

Humans evolved in an environment where they were exposed to animals, dirt, and a variety of pathogens and parasites. Our immune systems evolved to cope with that environment. Now most of us live in a different environment, with safe drinking water, flush toilets, food inspection, immunizations, and public sanitation. This means that we are far less likely than our ancestors to die of infectious diseases or to harbor intestinal worms. But it seems that the cleaner we get, the more likely we are to suffer from allergies and autoimmune diseases. One hypothesis is that our immune systems evolved to require early challenges by parasites and pathogens in order to develop properly. A hygienic environment fails to give our immune system the exercise it needs, resulting in imbalances and malfunctions.

The hygiene hypothesis was first proposed to explain observations like these:

  • Hay fever and allergies were less common in large families where children were presumably exposed to more infections through their siblings.
  • Polio attack rates were higher in high socioeconomic groups than in lower ones.
  • Allergies and many other diseases were less common in the developing world.

Investigation of these and other phenomena is contributing to a better understanding of the immune system, which is a good thing. At the same time, it has led some people to deliberately infect themselves with intestinal worms in an attempt to cure their allergies and autoimmune diseases, which may not be such a good thing. These treatments are far from ready for prime time, are risky, and they have a high yuck factor. The very idea of deliberately infecting yourself with worms is unpalatable, and finding wiggly live creatures in your stool or passing a 20 foot tapeworm are not generally considered to be pleasant experiences.  (more…)

Posted in: Book & movie reviews, Epidemiology, Evolution

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780.6. What is a fever?

You can tell what a doctor does for a living by the ICD-9 codes they have memorized. There is an ICD-9 code for nearly every medical condition. Weightlessness is 994.9. Must be there for NASA, I have yet to see a weightless patient. Decapitation by guillotine is E978. There, I suppose, in case Marat returns from the dead. There is an ICD-9 code for the initial visit after being sucked into jet engine (V9733XA) and one for subsequent visits (V9733XD). Why do I suspect V9733XD has yet to be used?

780.6 is my personal favorite. Fever. All my patients have fever and 780.6 was certainly the first ICD-9 code I committed to memory. I have an endless interest in fever and after last Fridays post I thought I would toss in my two cents worth. I will remind my readers that I am an adult ID doctor (who I treat, not necessarily how I behave) and unless specifically mentioned, all that follows applies to those who can legally drink, vote and serve in the military.

98.6 F. It is not normal body temperature. Well it is. But it is not. 98.6 F as average body temperature is an enduring medical myth. (more…)

Posted in: Basic Science, Evolution, History, Science and Medicine

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CAM and Creationism: Separated at Birth?

Over the past weekend, I had the opportunity to attend CSICon in Nashville, Tennessee. The Committee for Skeptical Inquiry (“CSI”) combats all sorts of pseudoscience, including creationism/creation science/intelligent design and alternative/complementary/integrative medicine. Our own Team SBM was ably represented by Harriet Hall, David Gorski and Kimball Atwood, whose presentation highlighted the credulous acceptance of CAM in some medical schools, and by Steve Novella, who gave a talk on the placebo effect and its exploitation by CAM proponents. Among many other presentations were those on the Mayan calendar and the end of the world, unmasking of (supposedly) paranormal events, and the neurobiology of memory. Pseudoscience was given a well-deserved thrashing by rational minds.

On Saturday, I once again had the pleasure of hearing Eugenie Scott ,Ph.D., the virtually one-woman anti-creationism campaign who founded and heads the National Center for Science Education (NCSE). As I listened to her talk I couldn’t help but being struck by a number of similarities in the weaknesses apparent in arguments for creationism/ creation science/intelligent design (or “ID”)and those for alternative/complementary/integrative medicine (or “CAM”). I doubt the two groups like to think of themselves as ideological twins, but gosh, they sure do look alike.

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Posted in: Evolution, History, Religion, Science and Medicine

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Thumbthing Worth Reading

I intended to read Sam Kean’s new book The Violinist’s Thumb: And Other Lost Tales of Love, War, and Genius as Written by our Genetic Code  just for fun. I was expecting a miscellany of trivia loosely gathered around the theme of DNA. But I found something much more worthwhile that I thought merited a book review to bring it to the attention of our readers. Kean interweaves entertaining stories into a somewhat disjointed but nonetheless valuable history and primer of genetics. The title refers to Paganini, whose DNA created the unusual joint flexibility that facilitated his unprecedented feats of virtuosity on the violin.

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Posted in: Basic Science, Book & movie reviews, Evolution, History

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Learning from Animals: Evolutionary Medicine with a Twist

In 2005, cardiologist Barbara Natterson-Horowitz was called to the zoo to examine a non-human patient, an emperor tamarin with heart failure.  She was surprised when the veterinarian told her not to look her patient in the eyes because eye contact could cause capture myopathy. In this condition, when an animal is captured, restrained, and feels threatened, there is a catastrophic surge of adrenaline that damages muscle tissues and can kill. It was described decades ago, but medical doctors don’t read the veterinary literature. It wasn’t until the early 2000s that American doctors began to recognize a similar phenomenon in human patients, takotsubo or stress-induced cardiomyopathy.

She began to wonder whether animals got other human diseases. She quickly learned that they did. Jaguars get breast cancer and may carry the same BRCA1 gene that plagues Ashkenazi Jewish women, rhinos get leukemia, penguins get melanoma, gorillas die from ruptured aortas, and koalas are in the midst of an epidemic of sexually transmitted chlamydia.  Wild dragonflies infected with parasites become obese and develop a form of metabolic syndrome. Pretty much every human disorder occurs in animals too.

With the help of writer Kathryn Bowers, she distilled her findings into a book: Zoobiquity: What Animals Can Teach Us About Health and the Science of Healing.  It’s a good read: informative, well argued, spiced with intriguing trivia, and more entertaining than a trip to the zoo. (more…)

Posted in: Book & movie reviews, Evolution, Veterinary medicine

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Do We Need “Evolutionary Medicine”?

3 years ago I wrote an article critical of “evolutionary medicine” as it was presented in a new book.   Recently a correspondent asked me if I thought another book, Why We Get Sick: The New Science of Darwinian Medicine, by Randolph M. Nesse, MD and George C. Williams, PhD, was a more reasonable approach to the subject. It was published in 1994 and got good reviews from respected scientists like Richard Dawkins (“Buy two copies and give one to your doctor.”) and E.O. Wilson (“bringing the evolutionary vision systematically into one of the last unconquered provinces…”).  I was able to obtain a copy through interlibrary loan.

The book was interesting and gave me some things to think about, but it didn’t convince me that “Darwinian medicine” is a new science, that its existence as a separate discipline is justified, or that its unique approach offers any real practical benefits for improving medical care.

Why do we get sick? A simplistic view of evolution holds that it systematically eliminates any factors that decrease fitness for survival. So why does disease persist? Why didn’t we evolve to be “fit” enough to never get sick? Because evolution is not a straightforward process.

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Posted in: Book & movie reviews, Evolution

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Why haven’t we cured cancer yet? (Revisited): Personalized medicine versus evolution

About a year ago, I addressed what might seem to the average reader to be a very simple question: Why haven’t we cured cancer yet? As I pointed out at the time, it’s a question that I sometimes even ask myself, particularly given that cancer has touched my life. Three years ago, my mother-in-law died of a particularly nasty form of breast cancer. Even though I am a breast cancer surgeon, I still wonder why there was nothing that could save her (and there still is nothing that could have saved her, if it existed then) from a decline over several months followed by an unpleasant death. Yet, as a cancer researcher, I do understand somewhat. A couple of years ago, I wrote in depth about the complexity of cancer from a science-based viewpoint, as compared, of course, to the incredibly simplistic view that many purveyors of alternative medicine quackery promote as being The One True Cause of Cancer. As I put it at the time, shamelessly stealing from Douglas Adams: Cancer is complicated. You just won’t believe how vastly, hugely, mind-bogglingly complicated it is. I mean, you may think algebra is complicated, but that’s just peanuts to cancer.

I saw more evidence of that at the American Association for Cancer Research meeting last week. In fact, if there’s anything I’ve learned, it’s that developing personalized therapy for cancer is going to be a hell of a lot more difficult than we had ever suspected. Actually, it wasn’t just the AACR meeting that taught me this, but it’s as good a pretext as any to discuss some cool new science. I only wish it was science that pointed an obvious path forward to the development of personalized therapy. On the other hand, if it were easy then anyone could do the “personalized therapy for dummies” approach that, for example, Stanislaw Burzynski takes. Then there’s the even more ridiculously simplistic approach that certain practitioners of “complementary and alternative medicine” (CAM) take.

So why haven’t we cured cancer yet? Again? One reason that I discussed last time I covered this topic concerns a study that used the latest next generation sequencing (NGS) techniques to sequence seven aggressive and advanced prostate cancers. I described the results as these genomes looking like someone threw a miniature grenade into the nucleus of a prostate epithelial cell. In other words, these are some really messed up genomes. (I wanted to use another word to describe it, but this is a family blog—sort of, anyway.) I used this example to explain once again that cancer is not a single disease. It’s hundreds of diseases. Although there are common themes in how cells become cancerous, such as loss of responsiveness to growth signals with a resultant ability to grow unchecked, evasion of programmed cell death (apoptosis), inducing the surrounding tissue to provide a blood supply (angiogenesis), evading the immune system, and invading the blood or lymphatic systems to travel elsewhere in the body and take up shop in other organs, such as liver, lung, or bone, individual cancers acquire these necessary (to the cancer) abilities through many different mechanisms. For this reason, it’s completely ridiculous to speak of a “cure for cancer.”

It’s also the reason I expressed skepticism when Steve Novella discussed a potential universal anti-cancer drug. Ditto when the press breathlessly reports studies suggesting a “universal cancer vaccine.” While these sorts of research findings are promising, they need to be put into perspective. We’ve seen their like many times before, and various cancers are still deadly diseases. In fact, my career intersected with this sort of hype back in the 1990s, when I studied combining angiogenesis inhibitors with radiation therapy in experimental models of cancer in mice. For a period of time in the late 1990s, I lived the hype. Then reality, as it always does, brought us all down to earth. Now, 15 years later, we know that angiogenesis inhibitors, although useful, are not any sort of “magic bullet” cure for all solid tumors. Like many advances before, they have now taken their place in the armamentarium of anticancer drugs, more important than some but not as important as others.

It’s even more complicated than that.

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Posted in: Basic Science, Cancer, Evolution

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