“Do you have any last words for our listeners?” I asked my guest this, one of the nation’s leading cardiologists, at the end of my radio program earlier this year. Rarely did this question lead to controversy. It was a courtesy question, providing a last opportunity to encapsulate the previous thirty minute discussion into an easy-to-remember take home message. But this time I was surprised by the response, and many of my listeners quite upset by it, called the station afterwards to let me us know in no uncertain terms their displeasure.
“Yes…don’t take dietary supplements,” he said in no uncertain terms.
He said this with just seconds left in the program, with no time to debate the merits of his assertion. This was particularly strange because we had just finished discussing his use of niacin, a b vitamin, to lower total cholesterol and raise good cholesterol in his cardiac patients. Originally I had invited this cardiologist onto Healthwatch because I was impressed that his book had discussed the science around many non-pharmaceutical approaches to heart health (e.g. sleep, diet, exercise, niacin, emotions/stress) and that he could talk authoritatively about which conventional interventions had the best research behind them, and which to be wary of. The show had gone great up to that point, before he dropped this bombshell as the curtain fell.
Certainly he wasn’t suggesting that patients stop their physician-prescribed niacin, that anemic women stop taking iron, that vegans discontinue their vitamin b12. Yet he told his captive audience to unilaterally stop their supplements nonetheless. Why did this physician, so adept at parsing out the nuances in the scientific literature, make such a blanket statement, one that contradicts his own actions with his patients?
I would argue that there is a double-standard when it comes to the way scientific literature is viewed with regards to pharmaceuticals and natural medicines. Earlier in the program my guest brought up the current upsurge in interest in vitamin D supplementation. He discounted the scientific literature on vitamin D because most of the studies were observational studies. He asserted that most results from observational studies were eventually proven, in higher-quality randomized, controlled studies, to be wrong. In observational studies, low levels of vitamin D are associated with an increased incidence of multiple sclerosis, certain cancers, low bone density and increased mortality. But my guest is right that an association does not prove causation. And it is quite possible that correcting a vitamin D deficiency will not lead to a subsequent decrease in incidence of some of these conditions (just like some cholesterol lowering medications successfully lower cholesterol but do not lower mortality rates or cardiac events).
But how much of conventional medicine relies on observational studies? Prior to 2002 conventional hormone replacement therapy was seen as a wonder drug. Not only did it control hot flashes effectively, it was being promoted for heart and bone health as well, with an apparently stellar safety record. Yet most of these studies were observational. Did that cause conventional physicians to pause, as it would for vitamin D? Unfortunately no. They did not hesitate to dispense these medications for decades, medications that have since been shown, in better studies, to not only lack their purported protective benefits, but also to significantly increase the risk of breast cancer. Likewise, when doctors, starting in the 1950s, recommended that patients with high cholesterol eat a low-fat diet, making no qualifications about the type of fat eaten, or said to stop eating eggs, was this based on high-quality science? I don’t think so.
Given that natural medicines are routinely dismissed when they lack well-controlled, randomized studies to back their use, I wondered how much of conventional medicine is supported by randomized clinical trials (RCT). It isn’t as high as you might think. Most researchers believe around 30-40% of conventional medicine is supported by RCTs, the gold standard of research results. Another 40-50% is supported by some sort of compelling evidence (either empirical evidence or evidence of a lesser quality than RCTs), leaving 20% without either. Of course, some interventions–blood transfusions, certain surgeries, restarting someone’s heart–would for obvious reasons never be put through an RCT (just as it is difficult if not impossible to study diet and exercise in this fashion; or to devise an adequate placebo for interventions like acupuncture) and thus it would be foolish to assume that everything outside of the 30-40% gold-standard interventions is unproven. Far from it. But I’m guessing the use of hormone replacement therapy and the standard dietary advice, dispensed for generations, of indiscriminately eating less fat, were once considered part of this second category, supported by “compelling” evidence, and given the benefit of the doubt that Vitamin D is not given, for instance. And ultimately, like my guest warned about vitamins, they too were proven wrong, as I imagine many of the interventions supported by compelling evidence will be.
What am I trying to say here? I’m not asserting that the majority of conventional medicine is unproven, nor that natural medicine has the same amount of research behind it as conventional medicine. But I am asserting that medicine by necessity is a blend of art and science, that a reasonable medical approach uses interventions based on knowledge acquired in different ways, some empirically, some based on first principles, and some based on research of varying degrees of quality.
There are plenty of conventional interventions with little high-quality research behind them which are embraced and promoted, when, on the other hand, natural substances with a similar or greater level of research supporting them are rejected out of hand. The conventional medicine community wants to have it both ways. They purport that natural medicines are weak and ineffectual, no substitute for “real” medicine, yet somehow they want us to believe that they are also so powerful that they will interact and interfere with all of your prescription pharmaceuticals. This is not a scientific assertion. It is magical thinking, that conveniently dovetails with the agenda of professional organizations defending their turf.
Hopefully one day, pharmaceutical companies won’t shut down research studies before unfavorable data can be published or preemptively screen out people who are robust responders to placebo so as to exaggerate the benefits of their drugs. And hopefully one day physicians will look more evenhandedly at the data, and their educations will reflect the science dispassionately. For instance, if exercise and cognitive behavioral therapy show better results for mild to moderate depression than anti-depressants, if St. John’s Wort has equivalent benefits as Zoloft, that will be reflected in physician behavior.
The conventional medicine community knows that modifiable risk factors, diet and lifestyle, can dramatically diminish the incidence of our most common killers, diabetes, cardiovascular disease and many cancers. Far more than any drug. Given that fact, you would think medical schools, if professional politics weren’t involved, if they were dispassionately and objectively focused on teaching all current medical knowledge, would devote a considerable amount of physician education to nutrition. There is no way a physician could give adequate dietary and lifestyle advice in their ten minute visits with patients. But if they had a half hour I’m not sure they would know what to do with it, lacking the background to give diet and lifestyle prescriptions that will translate into modified patient behavior.
Of course there are many bogus practices and outlandish claims being made by natural medicine practitioners, and for that reason, among others, we should welcome greater scrutiny and scientific analysis of natural medicinal practices. Despite claims by many, there are more and more RCTs of herbs, supplements, acupuncture etc. and there should be. But we should also remember that many of the ways that naturopaths have been ahead of the curve, often by decades, is because of the conclusions we come to based on our first principles that underlie our view of the human body. Whether it be sounding the alert about the consequences of antibiotic overuse, the role of food intolerances in disease, or the benefits of probiotics, this medical knowledge now being supported by studies, was first intuited based on philosophical principles.
One of those principles is that if you suppress a symptom without addressing its cause it is likely that there will be unforeseen negative consequences over time. That isn’t to say that symptom suppression isn’t ever necessary or even lifesaving. But a patient should be given the whole picture when given an intervention, told both that a cortisone shot, for example, has an often miraculous ability to eliminate pain, but also that people who get them have a higher rate of injury relapse than those that don’t. This has been shown in studies, but other potential consequences can often be intuited prior to the conclusive research, whether it be blocking stomach acid secretion long-term or giving hormones that are molecularly dissimilar to what our bodies produce endogenously, both of which naturopathic physicians were warning about prior to the research vindicating our concern.
For those interested in learning more about which supplements have the best research to support their use, a good place to start would be the work of Dr. Walter Willett, professor of medicine at Harvard medical school, who has published over 1000 scientific articles on various aspects of diet and disease. He is the second most cited author in clinical medicine. My interview with him can be found here.