Do vitamins reduce the risk of cancer or heart disease?

It is a triumph of marketing over evidence that millions take supplements every day. There is no question we need vitamins in our diet to live. But do we need vitamin supplements? It’s not so clear. There is evidence that our diets, even in developed countries, can be deficient in some micronutrients. But there’s also a lack of evidence to demonstrate that routine supplementation is beneficial. And there’s no convincing evidence that supplementing vitamins in the absence of deficiency is beneficial. Studies of supplements suggest that most vitamins are useless at best and harmful at worst. Yet the sales of vitamins seem completely immune to negative publicity. One negative clinical trial can kill a drug, but vitamins retain an aura of wellness, even as the evidence accumulates that they may not offer any meaningful health benefits. So why do so many buy supplements? As I’ve said before, vitamins are magic. Or more accurately, we believe this to be the case.

There can be many reasons for taking vitamins but one of the most popular I hear is “insurance” which is effectively primary prevention – taking a supplement in the absence of a confirmed deficiency or medical need with the belief we’re better off for taking it. A survey backs this up – 48% reported “to improve overall health” as the primary reason for taking vitamins. Yes, there is some vitamin and supplement use that is appropriate and science-based: Vitamin D deficiencies can occur, particularly in northern climates. Folic acid supplements during pregnancy can reduce the risk of neural tube defects. Vitamin B12 supplementation is often justified in the elderly. But what about in the absence of any clear medical need?

Weekend Reading

The SBP post on “pH Balancing” is one of the most popular, with over 43,000 views views since it was posted in 2009. The topic seems to come up again and again because alternative practitioners promote ideas that are not reality-based. Unfortunately, some pharmacies sell products that are marketed based on this falsehood. If you see these products for sale, think about taking your business to a pharmacy that puts a higher priority on selling credible products.

Just a short update today. Here’s some link and clips from the past week:

The facts about alternative medicine

People have been living on earth for about 250,000 years. For the past 5,000 healers have been trying to heal the sick. For all but the past 200, they haven’t been very good at it.

– Dr. Paul Offit

Twenty years is a long time in medicine. I celebrated my 20th pharmacy class reunion last weekend. Of course reunions are time to reflect back to our early years as pharmacists. Lots has changed. Much of the therapeutics I was taught is now obsolete. In 1993, HIV was a death sentence and there were only three, largely ineffective drugs available. Thanks to new drugs, HIV can now be managed like a chronic disease, and some of my colleagues have HIV-focused pharmacy practices. The same dramatic changes have occurred in fields like cancer, and transplant medicine. And in some cases, the cause of disease has become more clear – my old textbooks make no mention of Helicobacter pylori as a cause of ulcers.

The practice of pharmacy has changed, too. On the positive side, pharmacists are working in new settings where they can focus on medication management, and not just dispensing prescriptions. Regulators are granting pharmacists the ability to take on new roles, and pharmacists are being compensated for more than simply “count, pour, lick and stick.” From that perspective, it’s a promising time to be a pharmacist. But there’s a much more disturbing side to the profession that’s emerging, too. Community (retail) pharmacy practice is under pricing and competitive pressure, and smaller pharmacies are being subsumed into big retailers where the pharmacy department is buried in the back – a loss leader to bring in patients, but hardly with a health-care focus. And most disturbingly, I see a move within retail pharmacy practice to leverage its professional credibility to sell all types of modern-day snake oil, ranging from detox kits and “cleanses” to dubious “food intolerance” testing. Homeopathic remedies (an elaborate placebo system of sugar pills) are increasingly found on pharmacy shelves, alongside real medicine. And don’t forget the enormous wall of vitamins that seems to get larger and larger. Yes, complementary and alternative medicine is booming, and pharmacy wants its share. Pharmacy regulators turn a blind eye. What do my pharmacy colleagues tell me? They’ll tell me it’s customer demand, and that they don’t recommend the quackery. To me, I see this trend as damaging the credibility of pharmacists in the eyes of the public and of other health professionals.

CAM for cancer is no alternative

One of the themes I’ve emphasized in many posts on this blog is that every treatment decision requires an evaluation of risks and benefits. No treatment is without some sort of risk: Even a decision to decline treatment has its own risks. And when a treatment has no demonstrable benefits, the risks factor more significantly into our evaluation. One of my frequent counseling challenges with patients is helping them understand a medication’s expected long-term benefits against the risks and side effects of treatment. This dialogue is most challenging with symptomless conditions like high blood pressure, where patients face the prospect of immediate side effects against the potential for long-term benefit. One’s willingness to accept side effects is influenced, in part, by and understanding of, and belief in, the overall goals of therapy. Side effects from blood-pressure medications can be unpleasant. But weighed against the reduced risk of catastrophic events like strokes, drug therapy may be more acceptable. Willingness to accept these tradeoffs varies dramatically by disease, and are strongly influenced by patient-specific factors. In general, the more serious the illness, the greater the willingness to accept the risks of treatment.

As I’ve described before, consumers may have completely different risk perspectives when it comes to drug therapies and (so-called) complementary and alternative medicine (CAM). For some, there is a clear delineation between the two: drugs are artificial, harsh, and dangerous. Supplements, herbs and anything deemed “alternative”, however, are natural, safe, and effective. When we talk about drugs, we use scientific terms – discussing the probability of effectiveness or harm, and describing both. With CAM, no tentativeness or balance may be used. Specific treatment claims may not be backed up by any supporting evidence at all. On several occasions patients with serious medical conditions have told me that they are refusing all drug treatments, describing them as ineffective or too toxic. Many are attracted to the the simple promises of CAM, instead. Now I’m not arguing that drug treatment is always necessary for ever illness. For some conditions where lifestyle changes can obviate the need for drug treatments, declining treatment this may be a reasonable approach – it’s a kick in the pants to improve one’s lifestyle. Saying “no” may also be reasonable where the benefits from treatment are expected to be modest, yet the adverse effects from treatments are substantial. These scenarios are not uncommon in the palliative care setting. But in some circumstances, there’s a clear medical requirement for drug treatment – yet treatment is declined. This approach is particularly frustrating in situations where patients face very serious illnesses that are potentially curable. This week is the World Cancer Congress in Montreal and on Monday there were calls for patients to beware of fake cancer cures, ranging from laetrile, to coffee enemas, to juicing, and mistletoe. What are the consequences of using alternative treatments, instead of science-based care, for cancer? There are several studies and a recent publication that can help answer that question.

Burzynski Clinic? Meet the Streisand Effect

In the rough and tumble world of blogging, debate and criticism is healthy. I know I’m a better writer and blogger because the feedback from blogging is immediate and public. Yet if you’re going to blog about science, particularly pseudoscience, you’re going to encounter people who don’t share your belief in critical appraisal. And when groups and individuals cannot defend themselves with scientific evidence, they occasionally react by trying to stop that discussion from happening at all. One of the core principles of scientific skepticism is the belief that all ideas can and should be subject to fair criticism. No testable claim may escape appraisal or critique. It’s a critical component of the scientific method itself:

…at the heart of science is an essential balance between two seemingly contradictory attitudes – an openness to new ideas, no matter how bizarre or counterintuitive, and the most ruthlessly skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense.

– Carl Sagan, The Demon-Haunted World, Chapter 17

Andy Lewis is a prolific skeptical blogger and inventor of the handy Quackometer, a website that analyzes any website, giving a rating based on telltale signs of quackery. Recently Andy blogged about Stanislaw Burzynski and his eponymous cancer clinic. Lewis detailed the story of a child with an inoperable brain tumor and the fundraising that is occurring to send this child to Burzynski’s clinic. The concern is that Burzynski’s cancer treatments consist of an unproven therapy he calls antineoplastons. Despite the lack of any objective evidence that antineoplastons are an effective cancer therapy, Burzynski offers this therapy under the auspices of a clinical trial. Astonishingly, patients must pay for the privilege of entering these trials – in the case of the child in question, the family is trying to raise £200,000.

Your Urine is Not a Window to Your Body: pH Balancing – A Failed Hypothesis

One of my first encounters with “alternative” health was the “pH balance” idea. A customer approached me at the pharmacy counter and asked for “pH test strips.” I asked him about kidney stones, diabetes – the usual reasons you test your urine. He told me he was healthy, and he was just monitoring his body’s “acid balance” and that he kept his body “alkali” to be healthy.  “You can’t change your body’s pH, sir – if your pH changes, you’ll die,” I explained, in my most reassuring pharmacist voice. “You don’t know what you’re talking about,” he snapped at me, “I adjust my pH all the time.” I handed over the urine testing strips, rang it into the cash register, and wondered, what is this guy talking about? Where did he get the idea he could manipulate his body’s acidity?

Oil of Oregano: All anecdotes, no science

Oil of oregano has been around for several years, yet its ubiquity in pharmacies makes it worthy of scrutiny.  Is there any plausible science to support the claims made about oil of oregano? Does it belong in pharmacies that offer medicines that are based on good science?