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Coenzyme Q10 for heart failure: The hype and the science

Could a product sold as a dietary supplement really be delivering the benefits that advocates have claimed for decades? That’s what you might be wondering about coenzyme Q10, following recent stories like:

What’s caused all the excitement about CoQ10 is the Q-SYMBIO trial, more properly called “The effect of coenzyme Q10 on morbidity and mortality in chronic heart failure”, presented at the European Society of Cardiology conference last month. I’d normally wait for the full article to come out, and will review it if possible at that time, but the results are too interesting to ignore so I’ll dive into the study and the reaction – which is equally as interesting for advocates of science-based medicine. (more…)

Posted in: Clinical Trials, Herbs & Supplements

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Kombucha: A symbiotic mix of yeast, bacteria and the naturalistic fallacy

Kombucha

 

If you grew up in the seventies, you may remember the same food fads as I do. There was the oat bran buzz that was replaced by the wheat germ movement, the family fondue set and the homemade yogurt maker. And for a while I remember my father making what I called “aquarium water” – a foul-looking jug sitting on the kitchen counter with a gelatinous white mass floating on top. Despite the assurances it was good for me, I declined the taste tests. They didn’t push it and I never volunteered to drink this “cure all”. I thought kombucha had gone the way of gelatin-based salads and entrees, until a friend told me she was drinking it. Not only is it still a home-brew darling, kombucha isn’t just for hippies: There’s probably some for sale at your local organic grocery. Yet after a bit of digging, kombucha culture still seems mired in the 1970′s. It’s still touted as a panacea, and it’s still one of the more questionable folk remedies out there. (more…)

Posted in: Nutrition

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A closer look at vitamin injections

Vitamins are magic. Especially when they’re injected. Roll up the sleeve, find a vein, insert a needle and watch that colourful concoction flow directly into the bloodstream. It may sound somewhat illicit, but that person infusing it is wearing a white coat, and you’re sitting in a chic clinic. There must be something to it, right? Intravenous vitamin injections are popular with celebrities and have even been described by Dr. Oz as “cutting edge”. Advocates claim vitamin injections can benefit serious conditions like cancer, Parkinson’s disease, macular degeneration, fibromyalgia, depression, and that modern-day obsession, “detoxification”. And vitamin infusions aren’t just for the ill. They’re also touted as helpful for preventing illness, too. A search for vitamin injections brings up millions of hits and dozens of advertisements. There is no question that vitamin injections are popular. But despite all the hype and all the endorsements, there is no credible evidence to suggest that routine vitamin infusions are necessary or offer any meaningful health benefit. Vitamin infusions are a marketing creation, giving the illusion you’re doing something for your health, but lacking any demonstrable efficacy. What’s more concerning, providers of vitamin therapies target their marketing at those fighting life-threatening illnesses like cancer, selling unproven treatments in the absence of good scientific evidence that they are beneficial.

The intravenous vitamin industry is a sideshow to science-based health care. Yes, there is an established medical role for injectable vitamins, though it’s no energy-boosting cure-all – they’re used to replace what we should obtain in our diet. As a hospital-based pharmacist I used to prepare sterile bags of total parenteral nutrition (TPN), a mixture of vitamins, carbohydrate, protein and fat that completely replaced the requirement to eat. TPN is effective, but not without risks, and far less preferable than getting your nutrients the old fashioned way – by eating them. There’s also the routine use of injectable vitamins like B12, or iron, all of which can be science-based when used to address true deficiencies, or to manage specific drug toxicities. And there is the therapeutic use of high-dose minerals like intravenous magnesium for acute asthma attacks. But there is no medical justification to infuse vitamins into a vein when you can more appropriately obtain those nutrients in your diet.
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Posted in: Herbs & Supplements, Naturopathy

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Is thyroid replacement a performance-enhancing drug?

Has one physician uncovered the secret to Olympic Gold medals? And is that secret as simple as undiagnosed low thyroid function? That’s the question posed in a recent Wall Street Journal column entitled U.S. Track’s Unconventional Physician. Like the story that Steven Novella described yesterday, this narrative describes the medical practice of Dr. Jeffrey S. Brown, who sees thyroid illness where others see normal thyroid function. He has his critics, but his high-profile athlete patients have won a collective 15 Olympic gold medals. Case closed & Q.E.D.? Not quite. The WSJ actually does a pretty good job questioning the validity of Brown’s claims, which are far removed from the current medical consensus:

In athletic circles, Brown is a medical hero. He’s a paid medical consultant to Nike. The most renowned running coach at Nike, Alberto Salazar, calls Brown the best sports endocrinologist in the world. And athletes in growing numbers are coming to share Brown’s belief that heavy training can suppress the body’s production of the thyroid hormone, leaving them too exhausted to perform at peak. On the wall of the medical office of Jeffrey S. Brown is a photograph of Carl Lewis, the nine-time Olympic gold medalist. Lewis is one of several former or current patients of Brown’s who have climbed the Olympic podium, including Galen Rupp, who won a silver medal in the 10,000 meters at the London Olympics. “The patients I’ve treated have won 15 Olympic gold medals,” said Brown. Among endocrinologists, Brown stands almost alone in believing that endurance athletics can induce early onset of a hormonal imbalance called hypothyroidism, the condition with which he diagnosed Lewis and Rupp. Brown said he knows of no other endocrinologists treating athletes for hypothyroidism, a fatigue-causing condition that typically strikes women middle-aged or older. Several endocrinology leaders had never heard of hypothyroidism striking young athletes.

Now when I read “unconventional” and “stands alone” my skeptical alarm starts ringing. There is no shortage of debate about thyroid disease, ranging from the utter nonsense offered by “alternative health” practitioners to valid scientific discussions about the thresholds where normal function is considered abnormal and subject to treatment. Brown is an endocrinologist, however, and he’s treating elite athletes who are pushing their physical conditioning far beyond that seen by most medical doctors and almost all endocrinologists. So what’s the basis of the concern? The WSJ story goes on to discuss two different issues: What the proper threshold is for thyroid disease, and whether thyroid replacement is performance enhancing.  Let’s take each of these in turn. I’ve covered thyroid diseases and its related pseudoscience before, and a summary of the standard approach is necessary before we look at the some of the broader questions that have emerged from the story. All I know about these patients is what the WSJ is describing, so for the sake of brevity I’m going to focus on the types of cases that Dr. Brown appears to be identifying and ignore other causes of thyroid disease, which would require different treatment approaches.

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Posted in: Medical Ethics, Science and Medicine

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What’s in your supplement?

When you pick up a bottle of supplements, should you trust what the label says?  While there is the perception that supplements are effective and inherently safe, there are good reasons to be skeptical. Few supplements are backed by good evidence that show they work as claimed. The risks of supplements are often not well understood. And importantly, the entire process of manufacturing, distributing, and marketing supplements is subject to a completely different set of rules than for drugs.  These products may sit on pharmacy shelves, side-by-side with bottles of Tylenol, but they are held to significantly lower safety and efficacy standards. So while the number of products for sale has grown dramatically, so has the challenge to identify supplements that are truly safe and effective. (more…)

Posted in: Health Fraud, Herbs & Supplements, Politics and Regulation

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Cranberry, the alt-med zombie

If there’s a characteristic that’s common among proponents of alternative medicine, it’s tenacity. The willingness to stick with an idea, no matter the evidence, must give one a certain clarity. The naturalistic fallacy is often the foundation. Natural is good, synthetic is bad, no matter the evidence. In some cases, in spite of the evidence. How one deals with contradictory evidence is an effective tool to differentiate between medicine and alternative medicine – given sufficient convincing evidence, medicine changes its practices. The same can’t be said for alternative medicine, where few treatments are ever discarded. Otherwise practices like homeopathy, acupuncture, reiki, and chiropractic would have disappeared long ago. It’s also why disproven products continue to have occasional resurgences in interest. Cranberry is one. It has been touted as a treatment and a preventative for urinary tract infections for years.  And it doesn’t seem to work – not well, and not reliably, if you look at all the trials. And that’s being generous, considering the poor quality of the evidence with its inherent biases. I know a dead parrot when I see one. Yet its advocates, mainly manufacturers (is there a Big Cran?) keep insisting it’s alive, supported by the occasional positive report that appears. With a new systematic review and meta-analysis that declares it’s effective, it’s time to update our review. (more…)

Posted in: Clinical Trials, Herbs & Supplements

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Behold the spin! What a new survey of placebo prescribing really tells us

One of the recurring topics here at SBM is the idea of the placebo: What it is, what it isn’t, and how it complicates our evaluation of the scientific evidence. One my earliest lessons after I started following this blog (I was a reader long before I was a writer) was that I didn’t understand placebos well enough to even describe them correctly. Importantly, there is no single “placebo effect”. They are “placebo effects”, a range of variables that can include natural variation in the condition being studied, psychological factors and subjective effects reported by patients, as well as observer bias by researchers studying a condition. All of these, when evaluated in clinical trials, produce non-specific background noise that needs to be removed from the analysis. Consequently, we compare between the active treatment and the placebo to determine if there are an incremental benefits, to which we apply statistical tests to determine the likelihood that the differences between the intervention and the placebo groups are real. Removed from the observational nature of the clinical trial, we can’t expect the observed “placebo effects” to persist, as they’re partially a consequence of the trial itself. A more detailed review of placebos is a post in and of itself, so I’ll refer you to resources that describe why placebo effects are plural, that placebo effects are subjective rather than objective and there is no persuasive evidence to suggest that placebo effects offer any health benefits. What’s most important is the understanding that placebo effects are a measurement artifact, not a therapeutic effect.

Placebo effects are regular topics within in SBM posts because an understanding of placebo effects is essential to evaluating the evidence supporting (so-called) complementary and alternative medicine, or CAM. As better quality research increasingly confirms that the effects from CAM are largely, if not completely, attributable to placebo effects, we’ve seen the promoters of CAM shifting tactics. No longer able to honestly claim that CAM has therapeutic effects, “treatments” such as acupuncture or homeopathy are increasingly promoted as strategies that”harness the power of placebo” without all the pesky costs or side effects of real medical interventions. But this is simply special pleading from purveyors and promoters. Unable to wish away the well-conducted trials that show them to be indistinguishable from placebos, they instead are spinning placebo effects as meaningful and worthy of pursuit – ideally with your favourite CAM therapy. Again, I’ll refer you to posts by David Gorski and Steven Novella who offer a more detailed description of how negative results can be spun to look positive. Because CAM’s effects are indistinguishable from placebo, we should not invest time and resources into pursuing them – we should instead focus on finding treatments that are demonstrably superior to placebo.

But what if physicians are already using placebos widely in practice? Setting aside the ethical issues for now, widespread placebo usage might suggest that physicians believe that placebos are effective treatments. And that’s the impression you may have had if you skimmed the medical headlines last week:

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Posted in: Clinical Trials, Epidemiology, Science and Medicine

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Anti-inflammatory drugs: A closer look at the risks

If science-based medicine reflects the application of the best evidence, then we should expect practices to change when new data emerges. In the long run that’s generally true, and the progressive gains we’ve seen in the management of disease reflect this. But in the short run, change can be maddeningly slow, and there are many areas of medicine where we could be doing a better job of applying what we already know to improve outcomes and reduce harms. One area where this is obvious is drug treatments, which can provide remarkable benefits but are also sources of significant harms.

Somewhat problematically, the real world is often the setting where the full extent of harms from treatments are identified. Bringing new drugs to market means tradeoffs: Do you demand larger and longer clinical trials to get as much information as possible about a drug before it’s sold? Or do you approve based on more preliminary, potentially weaker evidence, to meet (potentially) important patient need? There is no set formula or right answer to this questions – it’s ultimately a value judgement exercised by regulators like the FDA, who decide which drugs are allowed for sale (the benefits are assumed, overall, to exceed the harms) or removed for sale (when the opposite is felt to be the case).
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Posted in: Pharmaceuticals

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Calcium supplements and heart attacks: More data, more questions

Why take a drug, herb or any other supplement? It’s usually because we believe the substance will do something desirable, and that we’re doing more good than harm. To be truly rational we’d carefully evaluate the expected risks and benefits, estimate the overall odds of a good outcome, and then make a decision that would weigh these factors against any costs (if relevant) to make a conclusion about value for money. But having the best available information at the time we make a decision can still mean decisions turn out to be bad ones: It can be that all relevant data isn’t made available, or it can be that new, unexpected information emerges later to change our evaluation. (Donald Rumsfeld might call them “known unknowns.”)

As unknowns become knowns, risk and benefit perspectives change. Clinical trials give a hint, but don’t tell the full safety and efficacy story. Over time, and with wider use, the true risk-benefit perspective becomes more clear, especially when large databases can be used to study effects in large populations. Epidemiology can be a powerful tool for finding unexpected consequences of treatments. But epidemiologic studies can also frustrate because they rarely determine causal relationships. That’s why I’ve been following the evolving evidence about calcium supplements with interest. Calcium supplements are taken by almost 1 in 5 women, second only to multivitamins as the most popular supplement. When you look at all supplements that contain calcium, a remarkable 43% of the (U.S.) population consumes a supplement with calcium as an ingredient. As a single-ingredient supplement, calcium is almost always taken for bone health, based on continued public health messages that our dietary intake is likely insufficient, putting women (rarely men) at risk of osteoporosis and subsequent fractures. This messaging is backed by a number of studies that have concluded that calcium supplements can reduce bone loss and the risk of fractures. Calcium has an impressive health halo, and supplement marketers and pharmaceutical companies have responded. There are pills, liquids, and even tasty chewy caramel squares embedded with calcium. It’s also fortified in foods like orange juice. Supplements are often taken as “insurance” against perceived or real dietary shortfalls, and it’s easy and convenient to take a calcium supplement daily, often driven by the perception that more is better. Few may think that there is any risk to calcium supplements. But there are now multiple safety signals that these products do have risks. And that’s cause for concern. (more…)

Posted in: Herbs & Supplements, Nutrition

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Who takes dietary supplements, and why?

If you’re a regular reader of this blog, I’ll bet you’re not a regular consumer of vitamins or supplements. I’m in that group. Aside from sporadic vitamin D in winter, I don’t take any vitamins or supplements routinely, nor do I give any to my children. Your reasons may be close to mine: There is little to no evidence suggesting that dietary deficiencies are widespread, nor is there good evidence to suggest that vitamin supplements are beneficial in the absence of deficiency. I don’t have any need for an other supplements, nor am I confident in the scientific evidence for many of them.This position of “no supplements” is a cautious and conservative one, but is based on a consideration of the scientific evidence. I view decisions about healthcare as evaluations of risk and benefit, and then cost if necessary. Given supplementation (with some exceptions) has no demonstrable benefits and, in some cases, a little risk, the odds favour not supplementing in most cases. Add in costs, and it’s even less attractive as a routine health strategy.

Yet a decision not to take vitamins or supplements regularly is becoming a minority position. Supplement use has grown over the past 40 years among Americans, with the National Health and Nutrition Examination Survey (NHANES) showing steadily increasing utilization among younger and older adults:
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Posted in: Herbs & Supplements, Nutrition, Science and Medicine

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