Are you taking vitamin D and calcium for bone health? If so, a new analysis makes it clear that the supplement guidelines you follow are often shaped by money rather than science. In July, Andrew Grey and Mark Bolland (University of Auckland, New Zealand) published an article in the British Medical Journal. Their article, “Web of industry-advocacy, and academia in the management of osteoporosis,” powerfully illustrates how industry ties and financial gain have tarnished the legitimacy of worldwide vitamin D and calcium supplementation guidelines.
The paper points out that, for at least the last five years, randomized controlled trials looking at vitamin D and calcium supplementation for osteoporosis have either demonstrated no benefit on fracture risk for subjects, or benefits so low that they are outweighed by the risk of other potential harms. Indeed, Grey and Bolland contend that even by 2007, the scientific community had little solid data upon which to recommend vitamin D and calcium supplementation, or a combination of both supplements, as a means of improving fracture risk.
By the end of 2010, however, fourteen large randomized trials on the topic had been completed. Three reported reduction in fracture risk, nine no effect, and two increased fracture risk. Smaller randomized controlled trials displayed the same trend. Additionally, a meta-analysis of 24 of these smaller trials was performed. When analyzed by intention to treat, it demonstrated either no effect of vitamin D and calcium on fracture risk, or an effect so small it was considered to be of “dubious clinical importance.”
Even these dubious benefits were effectively cancelled out by emerging data showing increased incidence of hospital admissions for GI symptoms, kidney stones, falls, hip fractures, myocardial infarction, and stroke among patients taking vitamin D and calcium for bone health. For example, 1 in every 178 patients taking vitamin D and calcium for bone health can expect to suffer from a vascular event while only 1 in 302 patients can expect one or a combination of the supplements to help prevent a fracture.
However, despite this strong evidence data against supplementation, over half of older Americans in 2015 regularly take calcium and vitamin D, most based on the belief that doing so will help their bones. How is this possible? To a large extent the answer appears to be money, or a combination of money and personal gain. Grey and Bolland searched the websites of key special interest groups, advocacy organizations, and consumer organizations that influence vitamin D and calcium supplementation guidelines in order to determine how commercial ties impact their recommendations.
First, they note the sheer amounts of money made by companies selling vitamin D and calcium. Global sales of calcium in 2013 totalled around six billion dollars. Those of vitamin D in 2012 brought in $748 million. However, companies that market food products high in calcium or vitamin D are pulling in hefty sums of money as well. For example, the dairy company Danone makes 13 billion dollars off its products, most of which are marketed “for optimal bone health” because they contain calcium and vitamin D. The companies and laboratories that make/use kits to test vitamin D levels also make a nice profit. In Australia, the annual cost of vitamin D testing increased from one million American dollars in 2001 to 96 million in 2010.
Grey and Bollard then examine the level and range of corporate sponsorship at several of the world’s leading osteoporosis foundations. The US National Osteoporosis Foundation states its goal is “improving patient outcomes.” Yet 12 of 22 NOF corporate sponsors are active in nutrition-related enterprises. Other members include companies that sell vitamin D test kits and supplement manufacturers. Interestingly the NOF website directly attempts to entice corporate sponsorship by offering these groups the opportunity to “influence the strategic direction of the organization at both formal and informal levels.”
It is hardly surprising then that the NOF and other related organizations such as the European-based International Osteoporosis Foundation (IOF) have failed to adapt their positions on calcium and vitamin D supplementation to reflect the growing body of evidence against their use for bone health. Instead, they continue to encourage high-level supplementation of these compounds without mention of possible side effects or harms.
The press releases and programs created by these organizations often directly attempt to suppress information from the public about the possible dangers now tied to calcium and vitamin D supplementation. For example, the Council for Responsible Nutrition (CRN) issued a 2010 press release in response to a meta-analysis that reported adverse cardiovascular outcomes among subjects taking calcium. The release urged readers that the negative findings “should not cause consumers to doubt the value of calcium supplements for maintaining bone health.” In 2011 yet more data emerged indicating possible cardiovascular harms from calcium intake. In response, the Council added a message to their website stating that the findings had “the potential to negatively influence consumers’ views of the importance of calcium.” They further called on member companies for whom calcium was key to their business ”to financially support an initiative to oppose potentially unwarranted media coverage on the topic.”
Grey and Bollard articulate how similar tactics are employed by other osteoporosis organizations. Particularly telling is that these public health organizations continually refer to the people they hope to influence as consumers rather than people or patients. Indeed, the word “web” aptly describes the manner in which these foundations corrupt the integrity of the recommendations they issue. The foundations themselves are kept in business by corporate sponsors that drive their recommendations. They are not required to disclose these conflicts of interest, and subsequently fail to do so on almost all levels. At the same time, academic researchers charged with studying vitamin D and calcium often either sit on or directly influence the boards of these organizations, without disclosing these additional conflicts of interest.
For example, academic researchers often partner with the CRN when conducting vitamin D research. The publications these groups produce acknowledge member affiliations but declare no financial conflicts of interest. Other groups of academic researchers are directly sponsored by companies that market dairy foods, nutritional supplements, or vitamin D testing kits. Yet even these more blatant industry ties are rarely disclosed in the biographies, journal articles, and speeches written and given by these apparently unbiased researchers.
In fact, according to Grey and Bollard, industry-supported advocacy organizations have gone so far as to re-write or re-interpret the results of studies on vitamin D and calcium so that their conclusions support outdated recommendations. For example, in 2013, a Women’s Health Initiative study on calcium and vitamin D for bone health found no overall effect of supplementation among participants. However, the NOF re-analyzed the study results to include only data derived from a small subset of subjects who benefitted minimally from supplementation. The new NOF version of the study fails to disclose any industry ties.
Even researchers not benefitting financially from vitamin D and calcium-related sales may still prosper academically from recommending their use. Many researchers have hinged their entire careers on the assumption that vitamin D and calcium are purely beneficial. It follows that the newer, emerging data suggesting against vitamin D supplementation may negatively impact their prestige or career development. Indeed, Gray and Bollard show that researchers with fewer direct ties to the vitamin D community are less likely to recommend supplementation when serving on public health committees.
It may be tempting for readers of this article to hope that some of these claims are overblown, but my personal experience with the vitamin D community suggests they are not. As someone who has published journal articles and given speeches against vitamin D supplementation since around 2007, I cannot overemphasize the negativity I’ve often run up against when trying to explain my perspective. In my personal experience, the worst offenders are members of the California-based “Vitamin D Council”, whose finances and public standing are so tied to the assumption that vitamin D is helpful that they blatantly mislead the public. Indeed, Grey and Bollard point out that the Vitamin D Council website does not acknowledge a single recent randomized controlled trial reporting no health benefits from vitamin D supplements. In 2009, I gave a five-minute speech at the Institute of Medicine (IOM) meeting on vitamin D. Members of the Vitamin D Council present were extremely unreceptive to my commentary.
Grey and Bollard point out that the Vitamin D Council website does not acknowledge a single recent randomized controlled trial reporting no health benefits from vitamin D supplements.
It’s worth noting that after this meeting, the IOM committee issued guidelines on vitamin D supplementation that differ substantially from those promoted by the other organizations mentioned in this article. As described here, after an evidence based analysis, the IOM committee was unable to support an association between vitamin D intake and improved health. They did not increase the Daily Recommended Intake of vitamin D, and further noted that vitamin D intake is associated with adverse health outcomes. While they reported a small positive association between vitamin D, calcium, and bone health, the association has been called into question by the results of more recent high-quality studies.
Unfortunately, few people I know are aware of the IOM guidelines on vitamin D, since the NOF, CRN, and Vitamin D Council promote their biased guidelines much more aggressively. This is a major problem. Again and again, I hear researchers reference the story of how, beginning in the 1960s, estrogen and progestin were promoted as a safe form of hormone replacement therapy. That was until a large 2002 trial reported significant adverse outcomes in women taking the drugs. Later it was calculated that before the dangers of the therapy were discovered, thousands of women suffered from breast cancer, heart attacks, or strokes as a result.
The story is often told as if the medical community has learned its lesson and another similar public health disaster is simply impossible. Yet, in the case of vitamin D, an alarming number of parties are sitting on inconclusive or negative data that they deliberately choose to ignore. In the meantime, radically high doses of vitamin D are regularly administered to members of the public who are often incorrectly informed about why they are being treated. Particularly alarming are cases where high levels of vitamin D are administered to nursing mothers or babies, despite the absence of any high-level evidence for its use by such parties.
As elections in the United States approach, much discussion on the world stage centers on attempts to remove special interest groups from the political arena. Clearly, the same level of concern must additionally be directed at the medical community. Conflicts of interest in the vitamin D debate may not only lead to physical harm for patients. As Grey and Bollard conclude, a failure to address the actual findings of the most current vitamin D and calcium research will ultimately erode public trust in the medical system as a whole. What a tragedy for all the well-meaning organizations and researchers who will suffer because of those who choose to play the system.