In one particularly effective passage, the story quoted a representative of a supplement industry group who disagreed with the report, saying that higher levels of vitamin D could be beneficial. But it then segued immediately into an explanation of why claims from supplementation advocates “are not supported by the available evidence.” The key problem, as the story points out, is that these claims are based almost exclusively on observational studies that can’t prove cause and effect and are often skewed by factors the researchers haven’t accounted for. Proponents of supplementation also have tended to downplay the possibility that higher doses of vitamin D and calcium might cause harm–a stance which the story notes may not be justified. We applaud this story’s effort to show readers where the weight of the evidence lies on this issue.
Vitamin D is the latest in a long line of “miracle” nutrients that people have turned to in the hope of improving their health. As we’ve learned from copious previous experience, these supplements rarely work as advertised and can sometimes cause harm at the higher doses people often think will be beneficial for them. More isn’t necessarily better when it comes to vitamin D–or most other health care interventions for that matter.
Most people know roughly what a bottle of vitamin D supplements might cost them, so the lack of information on cost is not a significant gap. We appreciate that the story provided data showing the large and growing amount our society is spending on vitamin D supplements ($430 million in 2009), with apparently little health benefit to show for it.
The story was mostly concerned with discussing the lack of benefit from taking extra vitamin D and calcium. And in this area it excels. While the story does lack precision when it suggests that adolescent girls should be getting more calcium (it never specifies how much they are getting now, how much more they’d need to meet the recommendations, or what benefits they might expect from this increased intake), it would be difficult for a journalist to come up with any sort of quantifiable benefit or harm estimate from the IOM report. The story captured the overall gist of the problem, which is that the evidence base is complex and still inadequate.
The story notes that, contrary to the claims of many advocates for increased supplemental vitamin D, there is evidence that high levels of vitamin D may have adverse effects, such as increased risk for fractures and an increase in the overall death rate. The story also explained that too much calcium has been linked to increased risk of kidney stones and, more tentatively, heart disease.
The story did a good job of describing how the expert committee conducted its review and what evidence they found. Importantly, it noted that claims of benefit from extra vitamin D are based on observational studies that most scientists agree “cannot determine cause and effect.” We also like that the story solicited opinions from a variety of experts with no obvious stake in the controversy. This produced a number of quotes that emphasized the need for restraint when interpreting the research on vitamin D. Examples: “I think this report will make people more cautious” and “The onus is on the people who propose extra calcium and vitamin D to show it is safe before they push it on people.”
Although we agree with the story’s skeptical overall message, we think it may have slammed the door just a bit too hard on the possibility of benefit from supplemental vitamin D. While claims of benefit may not be supported by the currently available evidence, they have not been conclusively disproved in randomized controlled studies, either. In fact, research is now underway to determine whether the benefits found in observational studies of vitamin D can be replicated in more rigorously designed trials. The story probably should have mentioned this research, and left the door to potential benefits open just a crack.
No disease-mongering here.
The diversity of independent voices included in this story is a real strength. Although it solicits the obligatory comment from a supplement industry spokesman, it didn’t go out of its way to find any of the more widely known vitamin D experts, some of whom have been issuing recommendations that are untenable based on current evidence. The enthusiasm of some of these researchers might be explained by their significant career and financial interests in promoting vitamin D.
Not applicable for this story. The approaches discussed are not new, and there’s not really any alternative to getting adequate amounts of these essential nutrients.
The availability of vitamin D from diet, sunlight and supplements is clear from the story.
The novelty of vitamin D and calcium is not really in question, so we’ll call this not applicable.
This story was not based on a news release.