More Controversy Regarding the Vitamin D RDA  

Toronto Globe and Mail

Recently there have been very negative articles in the Toronto Globe and Mail about vitamin D. They are, in part, a reaction to the ad campaign by Pure North S'Energy Foundation, a Canadian non-profit organization trying to convince Health Canada and the Institute of Medicine (IOM) to reconsider the RDA. There is also a petition, which we have featured and you may have signed, to ask Health Canada and the IOM to re-evaluate the data and reconsider their recommendation. It currently has over 6,300 signatures.

Ad that ran in Globe and Mail - click to view full size

Apparently we struck a nerve.

And the response from the general media was not positive.

The first article, an opinion piece by Andre Picard, published March 17th, makes claims we have heard before. High vitamin D levels aren't necessary; taking too much vitamin D can cause kidney stones; disappointing clinical trials; and the U.S. Preventive Services Task Force says testing is not necessary. In fact, in his caution that correlation does not equal causation, Picard seems to disregard any positive value of correlation. In his own words: "What this observational research shows is that people with adequate vitamin D levels have lower rates of a wide range of chronic illnesses. Stated simply, healthy people tend to be healthy."

Another ad that ran - click to view full ad

The second article was published this past Sunday, March 29, 2015, in the Health section of the Globe and Mail. In the article, "The vitamin D dilemma: How much should we be taking?" Leslie Beck summarized the conclusions of Paul Veuglers' paper published last October in the journal Nutrients as well as the letter from Robert Heaney, et al., published in the same journal last month - which both concluded that the IOM's RDA was off by an order of magnitude. The article also explains why we need vitamin D, continuing research in the field, and current concerns of harm resulting from too much vitamin D. She reports that both Health Canada and the IOM have indeed re-analyzed their data on the tails of Veugelers' paper and that "After formal reviews, both Health Canada and the IOM concluded that no statistical error was made." Furthermore, Health Canada noted that "there was no evidence that increases in vitamin D intake for obese persons beyond the requirements for non-obese individuals affect bone health or other health conditions."

According to Health Canada, "the analysis by Veugelers and Ekwaru greatly overestimates the amount of vitamin D needed for most people and intake at these levels would increase the risk for adverse health effects for some people."

IOM's Response    

The IOM updated its web site on March 20, 2015 to explain how it reached its recommendation of 600 IU/day - and has no apologies or acknowledgement of any criticisms or mistakes. They maintain that anything over 4,000 IU/day can be dangerous. Read this response for yourself. Typically a formal response would clearly state that it is a response and reference what it is responding to, it would be sumitted for publication, peer-reviewed and include the authors' names. This web posting did none of those things.

Responses from Scientists on GrassrootsHealth Panel

A response to the second newspaper article was posted on the Globe and Mail web site by Reinhold Vieth, PhD, Professor, Departments of Nutritional Sciences, Department of Laboratory Medicine & Pathobiology, University of Toronto:

"I have been a scientist focusing on vitamin D for the past 40 years, and have published more on its efficacy and its toxicity than anyone else in Canada. I am quite shocked at the very one-sided representations put forth by the Globe and Mail by Andre Picard and Leslie Beck. Shortly after the latest vitamin D guidelines were published at the end of 2010, it was Walter Willett of the Harvard School of Public Health, who pointed out in emails to other researchers the error that Veuglers et al. so nicely published recently. Anyone who cares about this subject must read the article about this by Robert Heaney, a highly esteemed nutritional investigator in the field of nutrition.

"Back in 2004, my own group in Canada published the first clinical trial using the 600 IU/day of vitamin D that is now the RDA. That work showed clearly that this dose does not suffice as the RDA to assure the 50 nmol/L blood level for adults. All that Veuglers and the Pure North group's advertisements have been doing was to point out that the RDA for vitamin D is like the emperor with no clothes. All that Leslie Beck and Andre Picard are doing is pretending that the emperor looks pretty well dressed to them."

Robert Heaney, MD, Professor of Medicine, Creighton University and Research Director, GrassrootsHealth, commented on the IOM's statement:

"What the IOM seems to be saying is that their calculated RDA will not actually meet the needs of 97.5% of the population. In effect, they admit their error, but assert  that it wasn't actually an error. They say instead that an RDA shouldn't get 97.5% of the population above the lower boundary of adequacy.  This is news to those of us who have been involved in the process.  In its other authoritative publications, the IOM defines an RDA (see the DRI book published by the IOM in 2006) as the intake that is 2 standard deviations above the estimated average requirement. That, in standard statistics, means an intake adequate for 97.5% of a population. I'm afraid their response is just double talk."