April 15, 2015

Letter from the Director


Dr. Joseph Mercola has put GrassrootsHealth in his new book, Effortless Healing, with a reference to our dose/response chart and, of course, to our D*action study for vitamin D testing.

This is a very personal
Thank YOU, Dr. Mercola, for your ongoing efforts to spread the word about vitamin D and, GrassrootsHealth. 


My first visit with Dr. Mercola was for an interview, Vitamin D and Cancer, primarily about cancer risk reduction.  Since that time, he has actively promoted our work to all his subscribers, and, a significant number of the subscribers are now part of the D*action project.  Recently he interviewed another member of our scientists' panel, Dr. Alexander Wunsch (see video link in the sidebar).  The growth of the D*action project with his help has significantly contributed to the information we now have to address the dose/response information factually and to help correct the issue with the statistical error by the IOM.


The focus of the book is a belief in the capability of the body to heal itself--with just a little bit of help from us!  As many of you know, this belief in our body's own capabilities vs. drug treatments is what initiated the GrassrootsHealth project to solve the vitamin D deficiency epidemic--it's simple and inexpensive and still needs our attention.  'Let your body do the work'-- it's time.  Please take a look at the simplicity of being a healthy person, it's available to everyone.




Carole Baggerly 

Director, GrassrootsHealth

A Public Health Promotion & Research Organization

Moving Research into Practice NOW!

How much vitamin D should I take? 


One of the most common questions we receive is how much vitamin D should I take to get my serum level to the desired range (40-60 ng/ml)? There is no simple answer, no magic bullet, as everyone's body is different. But here is the information you need, from our D*action data, to help you find a starting point to optimize your vitamin D level.


Recorded Supplementation vs. Serum Level


Using D*action data for 3667 participants, we plotted daily vitamin D supplementation (as reported in the questionnaire) vs. serum levels (as determined by our test). The main conclusion is that results from supplementation can vary greatly from person to person.



You may click on the graph to see a bigger view. The best-fit line (middle line) represents the average serum level (y-axis) for a particular vitamin D supplement amount (x-axis). The 25(OH)D value at zero supplement value on the x-axis (33 ng/ml) reflects vitamin D input from UVB exposure and food.   


In a paper titled "Vitamin D Supplement Doses and Serum 25-Hydroxyvitamin D in the Range Associated with Cancer Prevention"  two points were illustrated by this graph:

  1. The tendency for serum 25(OH)D to rise with increasing dosage is much more gradual at higher serum levels than at the lower levels.
  2. There is a very large spread of 25(OH)D values at each intake amount
Using this data, we added 95% probability bands (outer lines) that provide information regarding the doses required to ensure that 97.5% of the population would have 25(OH)D concentrations above a given level. In that graph, the lower band crosses 40 ng/ml at 9,600 IU/day, therefore, 9,600 IU/day is the supplemental intake that ensures that 97.5% of the population would reach 40 ng/ml. For the IOM, with a goal of 97.5% above 20 ng/ml, the amount of vitamin D (all sources) should be approximately 7000 IU/day.   

How do I reach the optimal vitamin D blood level?


If there is no magic amount of supplement that will do the trick, then you have to test. The best way to begin is by doing a vitamin D test to find your baseline level - before you start taking any new supplements. Then, you use this chart to move your blood level to the desired range.



This chart is based on our data and assumes an adult of average size, 150 lbs. So if you are about that weight and your first test recorded 20 ng/ml with you taking 1000 IU/day but you want to move your blood level to 40 ng/ml, then you need an increase of 20 ng/ml. Reading the chart you see that you should increase your current supplementation by 2600 IU/day, making it a new total of 3600 IU/day. Again, the chart is based on averages and individual results vary - so after 3-6 months we recommend testing again to see if you have achieved the desired level.  


What about toxicity?  


This first graph shows that the rise in 25(OH)D with higher supplement intakes is very gradual and even with intakes well above 10K IU/day, very few people reach 200 ng/ml (the lower boundary for potential toxicity).

Average serum level using only sun exposure and diet


We do have a number of people in D*action who do not take any vitamin D supplements. That means that they get their vitamin D from sun exposure and food alone. There is a common belief that spending 15 minutes outside once a day with just your face and arms showing will provide adequate vitamin D. This is not what we have seen in our data. Instead, our data showed that while there are individuals at each time interval of sun exposure who will reach 40 ng/ml, the average level did not reach 40 ng/ml until a substantial amount of time was spent in the sun each day. This varies from person to person and many individual factors such as latitude, season, age and skin pigmentation affect how the sun's rays are metabolized through skin. However, since many of us cannot make that kind of time commitment to mid-day sun exposure, supplementation is the key for most of us to achieve optimal vitamin D status.  

Video of the Week 


Your Data Your Answers, Part I

Sharon McDonnell, MPH

Epidemiologist / Biostatistician at GrassrootsHealth


Watch Now


Sharon McDonnell has been in the field of public health for nine years and has been an epidemiologist / biostatistician at GrassrootsHealth for the past two years.  She received a B.S. degree in Psychobiology from UCLA and an MPH in Infection Diseases, specializing in epidemiology and biostatistics, from UC Berkeley. 


This video is part of a video series of webinars we launched in 2013. While it is not from this year, the data from the D*action study is still valid. This video provides additional information on all the points mentioned above in "How much vitamin D should I take?"


This presentation is a great overview of the data we have collected with D*action. We discuss our participants with respect to geography, average serum level, types of supplements, and other vitamin reactions.


Watch Now 


Editor's Letter 


I have been a daily subscriber to Dr. Mercola's newsletter for years and I also took a sneak peak at his book - Effortless Healing. I won't say I was surprised. If you follow Dr. Mercola you know his hot buttons. What is great about this book is that it is all in one place. Consolidated. Easy to read and understand. I am thinking..... wonderful present for those you love!


I am fond of writing about the importance of testing. Our family was very overdue and we finally sent our tests in at the end of March. There are five of us, so in our busy household this was an amazing feat. I lined everyone up in the kitchen and we had a blood assembly line. Of course my boys were competing for who had the biggest blood spot and how to best achieve this spot (should you swing your arm, use a certain finger, a certain part of the finger). Luckily none of my kids are squeamish - so this time I didn't have to deal with crying. I was pleasantly surprised to see that the kids and I were in the optimal range. Unfortunately, my husband was low - and so I need to remind him to supplement daily, since his work does not have a vitamin D break room on the roof of his building (I still think that is a fantastic idea). I was glad to see my daughter was within range, as we know that keeping blood levels between 40-60 ng/ml reduces breast cancer by up to 75%. Even though she has just turned 7, I know it is important to start early for optimal health.  


I will take another sample after the summer and see what they read. Hopefully my husband will have been more regular with his supplements, and the rest of us will have kept up our sunning so that we are sufficient in vitamin D, allowing our bodies to n

aturally fight disease.

Have a great week!


Susan Siljander       

Marketing Director, GrassrootsHealth

A Public Health Promotion & 

Research Organization  

Moving Research into Practice NOW!


Effortless Healing

New book by Dr. Joseph Mercola

Decades of Dr. Mercola's exerpience, now all in one place

Sidestep illness
Shed excess weight
Help your body fix itself

Read about the book here or order on amazon.com.
Order Your Home Vitamin D Test TODAY!
Your participation in this project funds all the GrassrootsHealth research and promotion.
Watch Interview
The Healing Power of Light

Interview with Dr. Joseph Mercola and Dr. Alexander Wunsch, MD
Wismar University


Watch Interview
Vitamin D and Cancer Prevention

Interview with Dr. Joseph Mercola and Carole Baggerly, Director GrassrootsHealth


Watch Interview
Do You Need a Vitamin D Supplement to Maintain Ideal Levels

Interview with Dr. Joseph Mercola and Dr. Robert Heaney


Vitamin D Supplement Doses and Serum 25-Hydroxyvitamin D in the Range Associated with Cancer Prevention
View Paper

Letter to Veugelers
Response to IOM about inadequate RDA
View Paper

Serum level - Intake Charts
Average change in serum levels based on intake
View Here

Average serum level by vitamin D supplement amount
View Chart

Average serum level by sunlight alone
View Chart

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Video of the Week

Your Data Your Answers, Part I

Sharon McDonnell, MPH

Epidemiologist / Biostatistician at GrassrootsHealth


Watch Now 

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You can prevent disease if just one more person finds out about the preventative properties of vitamin D and starts moving their blood serum levels to 40-60 ng/ml. 

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