Do you take a vitamin or dietary supplement? It’s increasingly likely that you do, as over half of all American adults took some sort of supplement over the past 30 days. Now there’s evidence to suggest that about one-third of all Americans are taking supplements and prescription drug at the same time, which is renewing questions about risks and benefits. The same study reveals that combining supplements and prescription drugs is more common among those with certain medical conditions, compared to those without.
Many of us supplement in the absence of evidence of benefit, or even medical need. For example, there is little persuasive evidence to suggest that routine supplementation with products like multivitamins is necessary. There are exceptions of course: Those potentially becoming pregnant, those on dietary restrictions (e.g., vegans), and those with demonstrable medical need are among the cases where there is a clear benefit to vitamin supplementation, for example. The majority of us take supplements, like multivitamins, for “insurance” rather than because we have a deficiency or medical need. The evidence for non-vitamin supplements, like herbal products, is just as questionable as it is for vitamins, with few products showing meaningful health benefits. Ultimately decisions about supplements come down to evaluations of risk and benefits. Since I started working as a pharmacist, I’ve always cautioned consumers about the quality concerns and efficacy with herbal products and supplements, and the resultant risks that make me very hesitant to suggest their routine use – especially when they’re combined with prescription drugs. Yet the evidence suggests that it’s occurring – with increasing frequency. (more…)
We saw it coming. The re-emergence of vaccine-preventable disease should surprise no-one that’s been following the anti-vaccine movement.
Rebutting anti-vaccine rhetoric feels like a Sisyphean struggle. Steven Novella likened it to a game of whack-a-mole, where the moles are the same old tropes that keep popping up, no matter how often they are refuted with facts. Vaccines are a remarkable success of modern medicine: They are health interventions that are both demonstrably effective and remarkably cost-effective. Vaccination has likely prevented more deaths in the past 50 years than any other health intervention. Smallpox was a ruthless killer that took 300 million lives, just in the 20th century alone. Today it’s gone – eliminated forever. And now there are now over two dozen diseases that are vaccine-preventable. They should be an easy sell, and to most people, they are. But the control of vaccine-preventable disease relies in part on herd immunity – sufficient immunization to stop the spread of infection (no vaccine offers 100% protection) and protect those that cannot be immunized. Even a modest number of unvaccinated individuals can lead to reemergence of disease. None of this matters to antivaccinationists, to whom vaccines are bad. Viewing anti-vaccine websites for only five to ten minutes can increase the perception of risk of vaccination, and decrease the perceived risk of omitting vaccines. It also lowers vaccination intentions. By changing perceptions of safety, the willingness to vaccinate decreases. Now imagine that someone you believe to be a health professional openly questioned the efficacy and safety of vaccines – would it reduce your willingness to vaccinate? The evidence says it does. And that’s why the modern practice of naturopathy or “naturopathic medicine” is so concerning. Naturopaths have opposed vaccinations since the invention of naturopathy – starting with smallpox: (more…)
Does Tamiflu have any meaningful effects on the prevention or treatment of influenza? Considering the drug’s been on the market for almost 15 years, and is widely used, you should expect this question has been answered after 15 flu seasons. Answering this question from a science-based perspective requires three steps: Consider prior probability, be systematic in the approach, and get all the data. It’s the third step that’s been (until now) impossible with Tamiflu: Some data was unpublished. In general, there’s good evidence to show that negative studies are less likely to be published than positive studies. Unless unpublished studies are included, systematic reviews are more likely to miss negative data, which means there’s the risk of bias in favor of an intervention.
The absence of a full data set on Tamiflu (oseltamivir) and the other neuraminidase inhibitor Relenza (zanamivir) became a rallying point for BMJ and the AllTrials campaign, which seeks to enhance the transparency and accessibility of clinical trials data by challenging trial investigators to make all evidence freely available. (Reforming and enhancing access to trial data was one of the most essential changes recommended by Ben Goldacre in his book, Bad Pharma.) In 2009, Tamiflu’s manufacturer, Hoffman-La Roche committed to making the Tamiflu data set available to investigators. Now after four years of back-and-forth between BMJ, investigators, and Roche, the full clinical trials data set has been made freely available. An updated systematic review was published today in BMJ (formerly The British Medical Journal), entitled “Oseltamivir for influenza in adults and children: systematic review of clinical study reports and summary of regulatory comments.” This will be a short post covering the highlights. As the entire study and accompanying data are freely available, I’ll await continued discussion in the comments. (more…)
“Will Tylenol harm my baby?”
Pharmacists are among the most accessible of health professionals, and so we receive a lot of questions from the public. No appointment required, and the advice is free. Among the most frequent sources of questions are women seeking advice on drug use in pregnancy. This is an area where some health professionals are reluctant to tread. Some prefer to redirect all of these questions to physicians. But physicians are not always easily accessible, and few want to make an appointment just to ask what appears to be a simple question: Is it safe, or not? Admittedly, addressing questions about drug use in pregnancy can be challenging. There are no randomized controlled trials we can look to — there’s only messier, less definitive data. Our responses are filled with cautious hedging about risk and benefit, describing what we know (and don’t know) about fetal effects. In the pharmacy, one of the most common questions from pregnant women is about the use of acetaminophen (aka paracetamol aka APAP), more commonly known by the brand name Tylenol. Google “Tylenol and pregnancy” and you get 4.8 million results. Which source should you trust? (more…)
I glanced at my pharmacy license recently, and noticed I became a licensed pharmacist almost exactly twenty years ago. Two decades seems like a long time to do pretty much anything, yet I can still vividly recall some of the patients I encountered early in my career, working evenings in a retail pharmacy that drew heavily on the alternative medicine crowd. It was the first pharmacy I’d ever seen that sold products like homeopathy, detox kits, salt lamps, ear candles, and magnetic foot pads. And the customers were just as unorthodox. There were some that told me they manipulated their own pH, and others that insisted any prescription drug was designed to kill. And there was a huge clientele that relied on the pharmacy for their “bioidentical” hormones. It was an instructive learning experience, as it was as far from the science of pharmacy school as you could expect to find in a place that still called itself a pharmacy. One of the really interesting aspects of that pharmacy was the enormous supply of vitamins and supplements for sale. It stretched over multiple aisles and even back into where the drugs were kept, as there were some brands kept behind the counter. This wasn’t for any regulatory reason – it was because these were the “naturopathic” supply, the brands often recommended by naturopaths. In order for this pharmacy to sell them they had to keep the products behind the counter, presumably to grant these supplements a veneer of medical legitimacy. After all, they were “special”, and had the prices to prove it. (more…)
Diets fail. Not just often, but almost always—90% of the time. If diets worked we wouldn’t have a worldwide obesity problem. And obesity is a problem that needs to be solved. The prevalence of obesity has doubled since 1980. As a public health issue, there are few determinants of illness that are more destructive, as obesity contributes to the growing rates of diabetes, heart disease, and even cancer. There’s no “one true cause” of all illness, but obesity comes pretty close. When people ask me for the single most important thing they can do for their health, my advice (after quitting smoking) is to (1) ensure you keep your weight under control and (2) exercise in any way possible.
Despite its tremendous impact on health, I’ve only blogged about obesity in an indirect way—by pointing out what doesn’t work. Dr. Oz is my perpetual source of bad health information with his regular promotion of bogus “weight loss” supplements like the green coffee bean “miracle”. I’ve also criticized eating programs like the fads of “Eating Clean”, gluten “intolerance”, or harmful diet delusions like “detox”. It’s the typical skeptical science blogger approach—spot pseudoscience, debunk it, and hope you did something good. But none of my posts have focused on what one should do—just what you shouldn’t. Weekly SBM contributor Dr. Mark Crislip recently commented that what we (SBM) support manifests in what we oppose. He’s right, because that’s the easy approach. Using the principles of science-based medicine, there’s an awful lot to oppose in the current writing and popular opinion on how to treat obesity. And my professional advice in the role of a pharmacist has been limited to steering people away from supplements, and then giving some basic advice about dietary planning. Anecdotes and platitudes. I admit that I’ve told patients to “eat less and exercise more”.
One of the encouraging shifts I’ve seen in health journalism over the past few years is the growing recognition that antivaccine sentiment is antiscientific at its core, and doesn’t justify false “balance” in the media. There’s no reason to give credibility to the antivaccine argument when their positions are built on a selection of discredited and debunked tropes. This move away from false balance and towards a more accurate reflection of the evidence seems to have started with the decline and disgrace of Andrew Wakefield and his MMR fraud. And there is now no question that antivaccine sentiment has a body count: Simply look at the resurgence of preventable communicable disease. Today, antivaccinationists are increasingly recognized for what they are – threats to public health. It seems less common today (versus just 5 years ago) that strident antivaccine voices are given either air time or credibility in the media.
But false balance on topics like influenza can occur without giving a voice to groups like antivaccinationists. A more subtle technique to shift perceptions is both widespread and hard to detect, unless you’re aware of it: the naturalistic fallacy, known more accurately as the appeal to nature. In short, it means “It’s natural so it’s good” with the converse being “unnatural is bad.” In general, the term “natural” has a positive perception, so calling a product (or a health intervention) “natural” is implying goodness. The appeal to nature is so common that you may not even recognize it as a logical fallacy. Unnatural can be good, and natural can be bad: Eyeglasses are unnatural. And cyanide is natural. Natural doesn’t mean safe or effective. But the appeal to nature is powerful, and it’s even persuasive to governments. If we believe that health interventions and treatments should be evaluated on their merits, rather than whether or not they’re “natural”, then decisions to regulate “natural” products differently than the “unnatural” ones (like drugs) makes little sense. Yet the Dietary Supplement Health and Education Act was a legislative appeal to nature, introducing a different regulatory and safety standard for a group of products while drawing a fallacious distinction with “unnatural” products like drugs. Canada fell for the appeal to nature too: It has the Natural Health Products Regulations which entrenched a lowered bar for efficacy and safety for anything a manufacturer can demonstrate is somehow “natural”. (more…)
One of these things is not like the other
Treating a fever with medication like Advil or Tylenol is reflex action when we come down with colds and influenza. But could treating fevers actually worsen an illness and contribute to its spread in the population? That’s the impression you may have gained from the headlines and press last week, where antipyretics (fever-reducing medications) were described as some type of “anti-vaccine”:
Fever-reducing meds encourage spread of flu: McMaster report
Taking over-the-counter flu medication to cut your fever might help you feel better, but it might not be so good for the people you come into contact with.
When it comes to fever, your mother really did know what’s best
Who would have thought that the simple giving of a fever reducing agent, to either one of our family members or ourselves before we go off to school or work, may inadvertently lead to the death of someone that we see that day?
Use of fever-reducing drugs may lead to tens of thousands more influenza cases
The bottom line is that fever suppression increases the number of annual cases by approximately five per cent, corresponding to more than 1,000 additional deaths from influenza in a typical year across North America.
It’s the time of year where if you’re not sick, someone you know probably is. The influenza season in the Northern hemisphere started out slowly, but seems to be accelerating and hasn’t peaked yet. Add that to cold viruses circulating, and you get the peak purchasing period for cough and cold remedies. John Snyder gave a nice summary of the evidence base for the common treatments a few weeks ago. In short, despite all the advertising, there is little evidence to suggest that most of the “tried and true” products we’ve used for decades have any effect on our symptoms. One of the most sensible developments that’s occurred over the past few years has been the discontinuation or relabeling (depending on your country) of cough and cold products for children. The rationale to pull these products is compelling: Cough and cold remedies have a long history of use, and were sold without prescriptions before current regulatory standards were in place. They were effectively grandfathered onto the marketplace. When it comes to their use in children, the data are even more limited. There are few published trials and the results are complicated by different age groups, irregular dosing, lack of placebo control, and very small patient numbers. What’s even harder to believe was that doses were based mainly on expert opinion, not data, and generally didn’t consider that children don’t handle drugs the way adults do. So why withdraw them from pediatric use, but not adult use? Like most regulation, it comes down to risk and benefit. Both are troubling for pediatric use. (more…)
Note to SBM’s regular readers: Today’s post revisits some older material you may have seen before. Happy New Year!
New Year, New You, right? 2014 is the year you’re finally going to get serious about your health. You’re winding down from a week (or more) of celebrations and parties. You’re pretty much recovered from New Year’s Eve by now. It’s time to make some resolutions. Conveniently, there is no shortage of solutions being advertised to absolve you of your sins while overhauling your body and soul for 2014: What you need to do is “detox”. You’ll see the detox kits at your local Whole Foods (or even your local pharmacy). Books, boxes or bottles, with some combination of “detox”, “cleanse” or “flush” in the product name. Supplements, tea, homeopathy, coffee enemas, ear candles, and footbaths all promise detoxification. The advertising suggests you’ll gain a renewed body and better health – it’s only seven days and $49.95 away. Or try to cleanse yourself with food alone: Dr. Oz is hyping his Holiday Detox plan. Bon Appetit is featuring their 2014 Food Lover’s Cleanse. Or what about that old standby, the “Master Cleanse”? It’s the New Year – wouldn’t a purification from your sins of 2013 be a good idea to start the year? After all, the local naturopath offers complete detoxification protocols, including vitamin drips and chelation. There must be something to it, right? (more…)