July 13, 2016

Director's Letter
Carole Baggerly
Director, GrassrootsHealth

There was a song that was on a 78 record that I had as a child, The Churkendoose (yes, I'm really that old..)
Well It depends upon, begins and ends upon,
It depends on how you look at things!

The vitamin D research community is literally 'shooting itself in the foot' by reporting trial results solely on dosage groups without also always showing the serum level analyses.  The dose/response variation as shown in our research and that of others shows a very large variation, a factor of six in terms of response.  One person can take 2000 IU/day and get to 20 ng/ml (50 nmol/L), another can take exactly the same amount, 2000 IU/day, and get to 120 ng/ml (300 nmol/L). 

If, for example I had two people taking 2000 IU/day and one got to 20 ng/ml, the other to 120 ng/ml, I'd tell you the average was 70 ng/ml.

If we had another group taking 4000 IU/day and both got to 70 ng/ml, I'd tell you the average was 70 ng/ml. 

We'd then say that there was 'no difference' in the two doses.  Really?  And, we'd expect no significant difference in the health outcomes?

Please look at the chart below to see how that scenario looks with the Hollis/Wagner pregnancy study (left hand side of the chart).
Click to Expand

An almost 'flat' health outcome chart when looked at by intake level.When we look at the same patients by serum level vs intake, there is a very large difference.

Today, we are pleading with the research community to address this issue so that the public health messages from vitamin D can truly be acted upon vs set aside for 'more research'!  If you are a researcher, please let  us know that you are indeed addressing this and, how you achieve it.  We'd love to hear from you. We'd also like to hear from you if you find obstacles in the way and would like some help in addressing them.

Our health depends upon--how you look at things!


Carole Baggerly 
Director, GrassrootsHealth
A Public Health Promotion & Research Organization
Moving Research into Practice NOW!
How do you know what to believe about vitamin D?

Too much information

It is hard to know what to do with nutrient related information these days. Is it correct? Would it help your health condition? With any nutrient, including vitamin D, you could search the Internet and find several positive and negative articles on its effect.

One thing we know at GrassrootsHealth, is that there IS ENOUGH evidence on vitamin D to act. Vitamin D is essential for not only muscular/skeletal conditions but also immune function. Most likely if you are reading this, you believe the same thing - but how do you articulate this to others, or keep your faith, on the eve of published "bad" findings.

Scan for "tells"

Just as a poker player watches their opponents for tells, so should you scan the news article or research paper for these basic tenants of nutrient research, as outlined by Dr. Robert Heaney in his paper Guidelines for optimizing design and analysis of clinical studies of nutrient effects.
Be wary of findings from any clinical trial with these common problems
  1. Bolus dosing (generally large, intermittent dosing) - immune function only improves with daily dosing of vitamin D. Yet many studies on muscular/skeleton hypothesis were very effective on bolus (weekly, monthly) dosing. For a more detailed explanation, read this newsletter.
  2. Hypothesis/goal does not mention change in nutrient status - this premise will be the core problem with items 4-6 below. Since vitamin D synthesis varies greatly for each person, the hypothesis cannot be by treatment amount (supplement intake) but instead needs to be investigated around achieving a certain serum level.
  3. No initial serum measurement - you can't measure change if you don't know the starting value.
  4. Participants are not deficient (<20 ng/ml) at the start - see Dr. Grant's comment below. Since an effective study would change nutrient status significantly, the study needs at least one group to start at the low end.
  5. Low dosing (under 2,000 IU/day) - may not move nutrient status significantly for enough of the study participants to observe any effect.
  6. Analyzed only by dosage/treatment group, not by serum level - we need to know what serum level our patients should achieve for the desired effect.
  7. Less than or equal to 6 months testing for chronic conditions and disease prevention - as Dr. Holick says so eloquently below, it takes time to change nutrient levels within the body.
  8. No mention of co-nutrients, no attempt to optimize co-nutrients - this criteria is not a reason to throw out the study, but it would be optimal to optimize co-nutrients.
Now what?
Most likely, trials with negative findings will have more than one of these tells. Knowing these tells will help you understand possible reasons why the research did not show promising results. On our documentation page we have links to charts and studies which you may find pertinent and helpful to share with family and friends. 
Scientist Editorial

GrassrootsHealth Panel of Scientists speak to what they deem are some of the most important of the Heaney criteria.
Dr.  Grant asks a jaw-dropping question - what are we trying to prove?

"Most vitamin D clinical trials were designed based on the guidelines for pharmaceutical drugs, rather than those for nutrients. Pharmaceutical drug trials assume that the trial is the only source of the agent and that there is a linear dose-response relation between agent and health outcome. Neither assumption is satisfied for vitamin D. Robert Heaney outlined the guidelines for nutrient studies in 2014 [Heaney, 2014]. One of the key points is that people enrolled in the studies should have low status of the agent of interest at the time of enrollment. Most vitamin D trials do not use that as a condition of enrollment. As a result, they mainly address the question: Does giving the average healthy population a modest amount of vitamin D reduce the risk of adverse health outcomes over a short time period? As shown by the analysis by Bolland [2011], the strongest effects will be found for those with low baseline vitamin D status. "

William B. Grant, PhD
San Francisco

Dr.  Holick addresses the need for a significant change in nutrient status - which doesn't occur with paltry treatment groups (400 IU, 800 IU)
"It is remarkable to think that treating a person with a sub-optimal dose of vitamin D for a few years would overcome the consequences of a lifetime of vitamin D deficiency that has been associated with increased risk for many deadly cancers, cardiovascular disease, neurocognitive dysfunction and autoimmune diseases. These chronic illnesses likely were initiated many years before they become manifest. Most of the meta-analyses reviewed by the authors were studies that were relatively short term and used suboptimal doses of vitamin D.
Bottom Line: Meta-Analyses and rehashed meta-analyses, including this one [Allan, 2016], that are promoted in the lay press as new studies, demonstrating that vitamin D has little health benefit beyond musculoskeletal health needs more scrutiny. Vitamin D has existed on this planet for more than 500 million years. Our hunter-gatherer forefathers outside every day were likely making thousands of IUs of vitamin D daily. Maasai herders have blood levels of 25(OH)D of approximately 40-50 ng/mL. To achieve this level an adult would need to ingest at least 2000 IUs of vitamin D daily; and if obese would require 5000 IUs daily. These are the doses of vitamin D that can sustain a blood level of 25(OH)D of at least 30 ng/ml which is thought to be required for the many of the non-musculoskeletal health benefits of vitamin D. This Narrative Review [Allan, 2016] did not consider the scientific literature on the biological functions of vitamin D and only focused on meta-analyses of studies that used suboptimal doses of vitamin D that either did not measure nor achieve a blood level of 25(OH)D of at least 30 ng/ml. Thus it
provides little insight into the non-musculoskeletal health benefits of vitamin D."

Dr. Michael HolickMichael F. Holick, PhD, MD
Professor of Medicine, Physiology and Biophysics; Director of the General Clinical Research Center; Director of the Vitamin D, Skin and Bone Research Laboratory; 
Director, Biologic Effects of Light Research Center
Boston University Medical Center

Editor's Letter
Susan Siljander
Marketing Director, GrassrootsHealth

My favorite comment from Dr. Grant was,

"Does giving the average healthy population a modest amount of vitamin D reduce the risk of adverse health outcomes over a short time period?"

It is the perfect comment regarding these studies that do not find vitamin D to be effective. Of course vitamin D isn't effective! A diet wouldn't be effective if you only decreased calorie intake by 50 calories/day (or some such paltry amount) for only one month. No significant change. So that proves that diets don't work - right? No, it proves that THAT DIET didn't work. Same with vitamin D... we need studies which conform to the Heaney criteria, but especially ones that move the vitamin D level over a large level, from deficient (< 20 ng/ml) to sufficient (> 40 ng/ml).

I hope you enjoy these discussions around studies. If you want to read more studies you can google "ncbi vitamin D" and you will have more studies than you ever wanted. But then remember to use the "tells" described above to either throw out the study or keep it in the running.

Have a great week!
Susan Siljander
Marketing Director, GrassrootsHealth
A Public Health Promotion & Research Organization
Moving Research Into Practice NOW!
Order Now
Your participation in this project provides information for your answers to D questions and helps fund the GrassrootsHealth projects.

Guidelines for optimizing design and analysis of clinical studies of nutrient effects
Robert P. Heaney, MD
Creighton University
December 2013

Vitamin D Supplementation During Pregnancy:  Double-Blind, Randomized Clinical Trial of Safety and Effectiveness
Bruce W. Hollis et al.
Journal of Bone and Mineral Research
October 2011

A Randomized Trial of Vitamin D Supplementation in Two Community Health Center Networks in South Carolina
Carol L. Wagner et al.
Am J Obstet Gynecol.
February 2013
Read Paper

Post-Hoc analysis of vitamin D status and reduced risk of preterm birth in two vitamin D pregnancy cohorts compared with South Carolina March of Dimes 2009-2011 rates
Carol L. Wagner et al.
Journal of Steroid Biochemistry & Molecular Biology
January 2016

Health Characteristics and Outcomes of Two Randomized Vitamin D Supplementation Trials During Pregnancy: A Combined Analysis
Carol L. Wagner et al.
Biochemistry & Molecular Biology
July 2013

Click here to receive weekly news from GrassrootsHealth.
Share this Newsletter
Share this newsletter on Facebook!  

Click on the top left social share buttons
to share this entire newsletter.
Like us on Facebook

Follow us on Twitter

View our videos on YouTube
Contact Us