I asked Winnie to let me write a post on the most recent volley in the ongoing vitamin war because it’s a hot topic that I know she’d want to address, but her passion for the subject of nutrition and supplementation might suggest bias. Being a meat and potatoes guy who defines proper nutrition as having a meal that includes one green vegetable, I’m not as emotionally invested in the subject as she is. For this and other reasons, the opinions expressed do not necessarily reflect, etc., etc.
The health and nutrition online community has been on fire this week over three studies and an editorial published in Annals of Internal Medicine, and the resulting opinion pieces popping up in mainstream media sources including NPR (The Case Against Multivitamins Grows Stronger), UPI, Forbes (Case Closed: Multivitamins Should Not Be Used), CNN, The Guardian (Vitamin Supplements are a Waste of Money, Say Scientists), and the International Business Times, among many, many, many others. Basically, these hit pieces claim that people should stop taking supplements because these studies indicate that not only do they not prevent or cure chronic diseases, but they MIGHT. KILL. YOU!!!
As I said, I’m not deeply entrenched in the nutrition mindset, but even a cursory reading of these articles offended my intelligence, and suggests either an agenda or just plain sloppy science. There seems to be, for the record, a lot of evidence for the agenda theory in the general disdain much of Western medicine exhibits toward preventive health in general, and nutritional supplements in particular. As an old friend who worked in healthcare used to say, “There’s more money in treatment than in prevention.” Now, that isn’t to say that some nutritional products aren’t absolute garbage with no benefit to anyone but the manufacturer, and some are nothing but snake oil… but more about that later.
In the initial AIM editorial titled Enough Is Enough: Stop Wasting Money On Vitamin And Mineral Supplements, the writers – five MDs – reach some pretty bizarre conclusions based on the findings, and overlook some glaring flaws which the studies specifically acknowledge. The takeaway from the editorial, picked up and parroted uncritically by the mainstream media (I hate that term) seems to be that, since these studies don’t show definitive proof of benefit, you should stop taking vitamins IMMEDIATELY! Seriously, that was one of the conclusions reached in the AIM editorial:
“Evidence is sufficient to advise against routine supplementation, and we should translate null and negative findings into action. The message is simple: Most supplements do not prevent chronic disease or death, their use is not justified, and they should be avoided. This message is especially true for the general population with no clear evidence of micronutrient deficiencies, who represent most supplement users in the United States and in other countries.”
It’s hard to know where to start with this. The biggest issue I have with the entire editorial is the way they make categorical assertions based on tentative observations. That irritates me.
First example, “evidence is sufficient…” Not according to the studies they cite. In the cardio study, the researchers warn that “There was considerable nonadherence and withdrawal, limiting the ability to draw firm conclusions (particularly about safety),” and conclude with “High-dose oral multivitamins and multiminerals did not statistically significantly reduce cardiovascular events in patients after MI who received standard medications. However, this conclusion is tempered by the nonadherence rate.” An odd point for the reviewers to overlook. (Additionally, the test subjects were… not representative of the general population. Average age of 65 with at least one heart attack under their belts, most also suffered from hypertension, high cholesterol, diabetes, angina and / or congestive heart failure, and about half were already taking vitamins and / or prescription medications regularly – just sayin’)
“Most supplements do not prevent chronic disease or death.” Ya think? I’m not aware of any reputable supplements that make that promise. Nutritional supplements are called that for a reason – they are intended to supplement one’s nutrition. And it’s established fact that proper nutrition is one of several measures, including exercise, not smoking, limiting alcohol intake, and so on, used in conjunction to help prevent or mitigate the effects of chronic diseases. As Cara Welch of NPA (Natural Products Association) put it in her response to this article, “The intention of supplements is to supplement the diet. Don’t expect supplements to cure the common cold or prevent cancer, but they are part of the puzzle of a healthy lifestyle.” I also have a minor quibble with the implication that, even if they don’t cure cancer, one should avoid supplements entirely.
“This message is especially true for the general population with no clear evidence of micronutrient deficiencies, who represent most supplement users in the United States and in other countries.” Technically correct, as they say, is the best kind of correct. However, there’s a little more to the picture than that. One example: According to the CDC, 37.7% of American adults consume less than one serving of fruits and vegetables per day. The median consumption rate of all adults is 1.1 times per day for fruit and 1.6 times per day for vegetables. The numbers are slightly lower for adolescents.
This falls far short of the recommended 5-9 servings set out in the Food Guide Pyramid for optimal nutrition, so how might one <ahem> supplement this?
As to the categorical assertion that “Beta Carotene, vitamin E and possibly high doses of vitamin A supplements are harmful,” reputable sources tend to be a little less absolute in their language, generally suggesting that a substance may be harmful, or even toxic, under certain circumstances and / or in certain quantities. (If I were feeling glib, I’d say that the same applies to water) Take, for instance, the Mayo Clinic’s less alarmist interpretation of research on vitamin E, which states that, “Evidence suggests that regular use of high-dose vitamin E supplements may increase the risk of death from all causes by a small amount, although human research is conflicting. Caution is warranted.” The National Institutes of Health is equally cautious regarding the possible adverse effects of Beta Carotene, although it does recommend not taking it long term in high doses.
Let me be clear: as with most things, of course there’s a level at which therapeutic becomes toxic, and everyone should be mindful of the levels of anything they’re ingesting; I’m specifically addressing the absolute statements made in the AIM editorial.
One last thing that disappointed me was the implication in the studies (most studies I’ve seen, in fact) and articles is that a vitamin, is a vitamin, is a vitamin. That’s known to be so obviously incorrect that I have a hard time believing that it wasn’t intentional. Because of the lack of stringent regulation on nutritional products, quality, potency and content of multivitamins vary widely by manufacturer, and in some unfortunate cases, by batch. Very few manufacturers adhere to standards beyond the FDA Good Manufacturing Practices for dietary supplements. A common criticism of these studies is that they are often less than selective in the quality and type (EG – synthetic vs. natural, stand-alone vs. used in conjunction with others) of vitamins and minerals that they use, and then use them in a way that is inconsistent with standard practice. If anything, the takeaway from this is to be selective about the supplements you take.
As I alluded to at the beginning of my magnum opus, I’m no expert in either nutrition or clinical research, but even I can spot a contrived conclusion. As I also said earlier, there’s a perceived bias in Western medicine towards treatment over prevention. Beginning in med school, practitioners are trained – and often incentivized – to take the pharma route in patient health, and many of these studies (often financed by Big Pharma) come to damning conclusions based on major flaws in methodology so articles like these tend to lack credibility in my eyes.
But as Dennis Miller used to say way back when he was still funny, “Of course, that’s just my opinion. I could be wrong.”