More on the Vitamin D Controversy
Filed under: General Health
I recently wrote a blog refuting the recent IOM report on vitamin D, because I believe, along with the leading vitamin D researchers, that the report was off-base and gave poor recommendations.
This belief caused a reader to issue a response to my blog in the comment section. I thought his comment, and my response, needed to be seen by those of you who don’t read the comments section of past blog posts! It is long and in-depth, but enjoy!
Hi Brian,
Let me first say I agree D3 is a worthwhile supplement to take on a daily basis, and I have no vested (i.e., career) interest in whether the recommended intake of D3 increases or decreases. I am simply a methodologist/statistician who thoroughly understands the methodological shortcomings of this literature. I have served as lead statistician on numerous studies out of endocrinology (among many other areas and disciplines) and simply let the numbers do the talking! What is provided below is my honest, unbiased methodologist’s view of the D3 literature.
With that said, I purchased your supplemental Nutrition Guide with Eric’s Show & Go that was filled with great information, but I cringed when you stated you can safely have serum 25(OH)D of 50-80ng/mL. You not only have an incredibly high range, but your language indicates individuals should be on the high end of this range. You even go so far as to insinuate a reader with serum 25(OH)D of 20ng/mL could never get into your recommended range without ingesting an unsafe dosage of D3.
Nevertheless, I digress. I believe you should reconsider your quick critique of the review article describing the Institute of Medicine’s (IOM) daily D3 recommendations, and, further, reconsider your own recommendations to your clients and readers! The IOM recommended an optimal serum 25(OH)D of 20ng/mL. This recommendation was not only to maximize protection to the public, but was based heavily on the consistently emerging body of literature suggesting the benefits of increasing D3 intake plateau with serum 25(OH)D around 20ng/mL. Thus, there is absolutely no reason to increase dosage to increase serum 25(OH)D if no additional benefit is observed. The IOM go on stating individuals can safely ingest to 4000IUs of D3 daily; however, this is the threshold where adverse events have been shown in the literature. That is, ingesting more than 4000IUs is associated increased probability of adverse events. In addition, you are clearly aware that studies have shown serum levels above 50ng/mL increase the probability of adverse outcomes (e.g., kidney stones), especially with younger adults, but whether you choose to recognize these studies is debatable.
There is no doubt in my mind that you already knew some (or all) of this information. Coming from someone who just plain understands research, I urge you to critique studies suggesting health benefits of D3 with the same rigor you applied to studies suggesting adverse events. Any D3 study suggesting an increased health benefit must be viewed with caution—aside from probably the benefits to bone health, which has been shown to be a most consistent finding. No long-term safety studies for D3 have been published. This is a HUGE consideration. Further, you were quick to state that research suggesting adverse events with D3 supplementation are flawed methodologically, but you fail to state that ALL research is flawed. This includes studies suggesting health benefits of D3, which are essentially association studies that are inherently unable to imply causality. Further, if believe you are adequately critiquing the literature, you obviously know statistical significance (i.e., p < .05) means nothing. Thus, you already know that any D3 study with a large enough sample is guaranteed to indicate statistical significance. If you didn’t know this, however, then I recommend finding an individual with a background who can explain the literature to you, in an unbiased manner. It will make you a more informed nutritionist who is able to project ACCURATE information to your clients and readers!
Best,
Walt
Hi Walt,
While I appreciate the well thought-out comment, I do not appreciate the condescending tone. Yes I do understand the limitations of statistical significance, and I do know that most of the vitamin D data is based on observational studies, but there are actually many controlled trials on vitamin D supplementation above 600IU showing many benefits. As for pointing out the flaws, I simply stated that other vitamin D researchers have pointed out the flaws in the methodology, not me. I am not a vitamin D researcher.
However, here are a few items for you to consider. The IOM wants people between 20-29.9ng/mL because in their estimation that provided the best protection for bone health. However, There is a lot more to vitamin D than bone health.
Beyond that, there are many researchers on vitamin D who roundly disagree with the recommendation. One would be Robert Heaney of Creighton University, one of the leading bone researchers in the world. He recently wrote a letter to the Annals of Internal Medicine about some literature reviews that they had published on vitamin D. In it he stated that doses ranging from 4000-5000IU/day (to reach 30-40ng/mL)are not high, and are actually within our normal physiological range since these values are consistent with those found in healthy individuals living in conditions similar to our ancestors. He also pointed out that outdoor summer workers often have blood levels of 48 to 80ng/mL, without reported adverse affects. In fact, the National Institutes of Health states that the normal range for vitamin D status is 30-74ng/mL.
And since we are on the topic, lets take a look at a recent controlled trial on vitamin D supplementation. A recent 16 week study compared supplementation of 400IU/day to 2000IU/day. 2000IU/day beat 400IU/day in every measure. The vitamin D status in the 400IU group went from 13.6 to 23.9ng/mL (in your optimal range), while the 2000IU group went from 13.3 to 34.3ng/mL (in my optimal range). Aortic stiffness decreased and body fat mass was inversely associated in the 2000IU group, while the 400IU group actually had an increase in aortic stiffness and no association with body fat mass.
Granted that is one study (and there are many more), but it did find that more than 29.9ng/mL did provide greater benefit than being below it. Seems to be an additional benefit to me.
We also know that pregnant and lactating women need more vitamin D. It has been shown that breast-feeding women need at least 2,000 to 4,000IU/day to normalize their vitamin D status, and to normalize the vitamin D status of their feeding baby. Less than that is ineffective.
Now would I have worded the Show and Go recommendations differently if I were to write it now, probably yes, but I don’t think it was the evil you have made it out to be. To get from 20ng/mL to my stated range of 50-80ng/mL would take approximately 3000IU/day, which is below the IOM upper limit of 4000IU/day, how is this dangerous? You also state that research has clearly shown that intakes above 4000IU/day is associated with increased probability of adverse events. Where is this research? The IOM also stated that 10,000IU/day might lead to toxicity, yet they did not produce any reproducible evidence that that level has ever caused toxicity in humans.
The data on vitamin D is certainly not conclusive, but since we know that at least 30-40ng/mL (and higher) is normal in people living in conditions similar to our ancestors (ie – getting plenty of sunlight and eating real food), I don’t see how that range is dangerous. Might different populations have different ranges? Yes, possibly. Might being near 80ng/mL not be the best idea? Yes, possibly (though many researchers and the vitamin D council would disagree). Is 20ng/mL optimal? No, and the research does not agree with that (I just showed one example of many). What is optimal? It depends on many factors, but I think being anywhere from 30-50ng/mL is probably a pretty safe bet, though individual differences are definitely possible, and there are populations who might not want to elevate their vitamin D status.
To cap this off, the Institute of Medicine consulted with 14 vitamin D experts about their recommendations. These 14 experts all provided reports on the recommendation, and yet these 14 reports have been suppressed. They won’t let us know what these vitamin D experts (including Robert Heaney) had to say about their report, interesting… Also of note the Canadian Cancer Society, the Canadian Pediatrics Society, and Osteoporosis Canada all decided to maintain their current recommendations of 800 to 2000IU/day of vitamin D, despite the IOM report.
Like I said in the blog, get yourself tested. You should know your levels before you start supplementing, to know where you are compared to where you want to be. Discuss your results with your doctor, and most importantly, educate yourself.
Sincerely,
Brian
For more information on the topic, and for more reading from experts who roundly disagree with the report, see below. FNB stands for Food and Nutrition Board, which was technically the arm of the Institute of Medicine who released the report.
Comment on the IOM Vitamin D and Calcium Recommendations
Vitamin D Council Statement on FNB Vitamin Report
Statement on FNB Vitamin D Report
Statement on FNB Vitamin D Report: Bill Sardi
Why the New Vitamin D Recommendations Spell Disaster For Your Health
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Posted on December 17th, 2010 by Brian St. Pierre
9 Comments
December 17th, 2010 at 12:38 pm
Hi Brian,
I love your reply. A friend forwarded me an email on the IOM’s recommendations, and I was so outraged with the report that I had to reply. Here it is, in case you find it interesting.
Best Regards,
Kevin Greer
http://www.nytimes.com/2010/11/30/health/30vitamin.html?src=me&ref=general
Hi XXX,
This article is such a harmful abomination of science and logic, that I need to comment:
- Studies have found the NAS (of which the IOM is part) to be heavily influenced by firms involved with issues under recommendation: http://www.cspinet.org/new/200607241.html
Note: This appears to be the case here as well: http://donmatesz.blogspot.com/2010/12/institute-of-medicine-vitamin-d.html
- They acknowledge the strong epidemiological correlation between low-levels of Vitamin D and many diseases, but state that you can’t necessarily draw causation from correlation. However, the complete rule is that “you can’t draw causality from correlation, in the absence of mechanism.” Meaning that unless you have a plausible explanation for how the one factor contributes to the other, you can’t be sure that you’re not inadvertently attributing the cause to some third factor which affects both your presumed cause and effect, or even that you have cause and effect reversed. However, it would be completely disingenuous to make this claim against Vitamin D, given that it is only one of two chemicals for which every cell in the human body has a receptor (the other being Human Growth Hormone (HGH)). Vitamin D is involved in hundreds of biological processes, so you can’t really draw the “absence of mechanism” defence in this case.
- When the IOM issued their May 2004 report denying any causal association between autism and mercury exposure from childhood vaccines, their reasoning was based on epidemiological studies. They can’t have it both ways, depending on their desired conclusion. BTW, later studies would show that the IOM’s 2004 report was premature, based on preliminary incomplete information, and overstated its conclusions.
- They actually recommend tripling the US RDA for Vitamin D (from 200 to 600 IU’s) but then state that there’s no need for supplementation because almost everyone has the necessary 20-30 nmol/L blood serum level. That’s completely illogical and ill-founded on several levels. If levels are already sufficient, then why increased the RDA? If the RDA is increased, then how is this to be achieved without supplementation? The chart below shows how to interpret serum levels, and from the chart, you can see that 20-30 is nowhere near sufficient. A level of 60-95 is considered ideal (by some). At northern latitudes, it is nearly impossible to get adequate Vitamin D without supplementation; and literally impossible during winter. Even at lower latitudes, Vitamin D deficiency is rampant. A recent study showed that the majority of Miami residents also suffer from Vitamin D deficiency, despite the abundance of sunshine (apparently it’s too hot to go outside).
- These recommendations are for both the US and Canada, but how could you possibly have the same recommendations for both countries given the dramatic differences in Vitamin D producing sunshine? For that matter, how could you even have one recommendation for all of the US. Someone living in Alaska would have dramatically greater need for Vitamin D supplementation than someone living in Hawaii.
- Studies have shown that there are no signs of toxicity at supplementation levels of 10,000 IU’s per day over long periods of time, so what are trying to protect people from if they error on the side of going a little high? If I spend 20 minutes in the Summer sun, my body can generate 20,000 IU’s and I don’t get sick.
From: http://toronto.ctv.ca/servlet/an/local/CTVNews/20101130/institute-of-medicine-vitamin-d-recommendations-101130/20101130/?hub=TorontoNewHome
“There is also no mention of the fact that toxicity of vit D is associated with D2, not D3. There is not a single reported case of toxicity (of D3) at levels below 40,000 IU DAILY. In fact, many clinical trials use injections of D3 (100% absorbed) at levels of 200,000 IU.”
Natural News also comments on this report:
http://www.naturalnews.com/030598_vitamin_D_Institute_of_Medicine.html
December 17th, 2010 at 1:02 pm
Brian,
I was not expecting to see my comment posted outside of the comments section. It caught me off guard, but I appreciate your willingness to engage your readers in the debate.
What I want to say initially, is that I apologize to you for sounding condescending. This was never my intention, but when I re-read my comment, I can clearly see how it came across that way. Again, my apologies, you did not deserve that.
Second, I appreciate your willingness to pay attention to emerging literature, and I enjoy academic debates—especially ones where there are two clearly divergent camps. I especially liked how you explicitly stated Robert Heaney by name; however, I have to agree with JC Gallagher, another world-famous Vitamin D researcher out of Creighton University, who stated (in far more words and using the word “onus”), researchers who promote ingesting high doses of Vitamin D must show its safety. This comment specifically addressed the risk of adverse events associated with calcium and Vitamin D intake. Further, evidence is emerging stating the human body metabolizes Vitamin D from the sun differently than Vitamin D supplementation. It may, in fact, be a different process.
Bottom line, I have no doubt there is a risk-reward ratio with vitamin D intake. Finding the vertex of that parabolic function is the primary issue, and this is what is up for debate currently. I’ll be taking some time to review the studies you highlighted in your post, critiquing both positive and negative characteristics, and then get back to you. You referenced a number of studies, so this will take some time. As I said in my original post, I am not a Vitamin D researcher, I just know research and what it can (and cannot) tell you. This process will allow me to present my (better informed) unbiased opinion.
I appreciate the dialogue and have safe holiday season,
Walt
December 18th, 2010 at 11:27 am
Walt/Brian – Awesome info, very cool to see you guys being adults about this and not descending into internet mudslinging haha!
December 21st, 2010 at 5:40 pm
About a year and half or so ago, I started taking 5000IU’s a day. I got my vitamin D levels tested late last year via grassrootshealth.net. My test level was 68 (40-60 is their recommended range). My understanding is that darker skinned people (I”m black) may need to take higher dosages of vit d.
Regardless, I plan on taking 5000IU’s the rest of my life. Like you said, getting tested is important.
December 22nd, 2010 at 10:19 am
What are your thoughts on vitamins A and K? I have read a lot about Vitamin D from various sites like your own since the new recommendations have come out. The most compelling argument was that it is important to ensure vitamin D, A, K ratios are in balance. There’s no doubt that most people could use more D but what about A and K? Here are the articles
http://www.westonaprice.org/blogs/is-vitamin-d-safe-still-depends-on-vitamins-a-and-k-testimonials-and-a-human-study.html
http://www.westonaprice.org/blogs/are-some-people-pushing-their-vitamin-d-levels-too-high/
December 22nd, 2010 at 12:32 pm
Walt,
I look forward to your reviews. Something else that we have not touched on much that I think is important is vitamin D status relative to the other fat soluble vitamins. Jeff shared some good info that definitely raises the question of if people are adequate or deficient in vitamins A and K2 might make a huge difference in the results of the vitamin D research.
Ed,
Thank you. I think debate leads to increased knowledge for all.
Kujo,
As far as I know blacks might actually be better with slightly lower blood levels. There is some data, and a school of thought, that since blacks require significantly more sunlight to increase their d levels, that they might have evolved to require less vitamin D. Unfortunately the knowledge just isn’t there yet. We don’t the ideal ranges for everybody, let alone for specific populations. If you are feeling great and not having any side effects, then you can continue your regimen. If you develop any side effects, and even if you don’t, I would encourage you to decrease your dose and try to be right in the 30-50 range. Read the two links that Jeff provided, they are full of excellent information
December 22nd, 2010 at 12:40 pm
Jeff,
I definitely think that people need to ensure adequate intakes for the other fat-soluble vitamins. If you read my initial post I alluded to this:
All essential nutrients are part of a much larger whole, and work synergistically together, modifying each other’s effects. Taking huge doses without getting tested is probably not a good idea.
On top of that if people consume grass-fed meat and/or dairy, pastured eggs as well plenty of fruits and vegetables, they should get in adequate amounts of vitamins A and K2. I definitely think more research is needed on the topic, that is for sure.
I look at vitamin D supplementation as sort of substituting for the lack of sunshine that people get today. If you are supplementing with an amount that someone of your race or ethnicity could make in a reasonable amount of sunshine (~15-30 minutes), and you consume a whole-foods diet with adequate vitamins A and K2, you should be spot on.
December 22nd, 2010 at 4:37 pm
Thanks for the info Brian! Very interesting topic and blog!
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