February 24, 2016

Director's Letter 
Carole Baggerly 
Director, GrassrootsHealth 

The number one question I receive continues to be, "How much should I take?" The answer to that question also continues to be, "There is no magic amount. You have to find what works for you - what gets you up to 40 - 60 ng/ml." For the vast majority of people, it will be closer to 5000 IU/day, much more than the 400 or 600 IU found in most multi-vitamins. We've used your D*action data to create charts and calculators; tools to help provide a starting point or feedback for how your intake and serum level compare to others. But you still have to test, and it may take some trial and error to figure out what amount of sun, supplement and/or foods get your level in the 40-60 ng/ml range.
This is a process, like all health matters. It can't be determined overnight. You need to test, change habits, test again. 

D*action was created in 2009 as both a study platform and a way to provide inexpensive, at-home vitamin D tests. Some of our participants reported that in 2009 if they wanted to test their vitamin D through their doctors, it was not covered by insurance and cost hundreds of dollars ($500 for one test!). Thankfully, this is no longer the case. 

While you may be tested through your primary care doctor, it is now more important than ever to continue with D*action. The more participants we have who regularly test and report health outcomes (every 6 months is ideal) - the more powerful our data, our research, and our ability to reach out and spread the word.

You can make a difference, NOW! During the month of March we are offering a one-time test for 25% off ($48.75 plus $5 shipping). 

Your D*action will make a difference for you!

Carole Baggerly 
Director, GrassrootsHealth 
A Public Health Promotion & Research Organization 
Moving Research into Practice NOW!

Participant Story


Barbara Haplea 
Married 52 years, 3 sons, 4 grandchildren
75 years old
Huron, Ohio

How did you hear about GrassrootsHealth?

In August 2009 I found a lump in my breast, even though I had no history of cancer in my family. I had always been healthy, active (tennis, water ski) and lean. I was stunned. Looking back now I attribute it to the synthetic progesterone I was on for 11 years.

My treatment began with a lumpectomy in September, 2009. My treatment was part of a cancer clinic which held lectures and the following month I went to a lecture on vitamin D. It was there that I found a GrassrootsHealth lecture. My first blood test with GrassrootsHealth was in October 2009, and I have done them every 6 months since, a total of 12 tests. My next one is due in May of this year.

"GrassrootsHealth was the light at the end of the tunnel. It was the hope I needed in a time of great despair." - Barbara Haplea

When I went into that first lecture about vitamin D I was so confused and lost because no one knew how you get cancer, and no one can promise a cure. This left me without hope. I could not imagine how I was going to pull myself through this disease, and if I did how I would deal with the fear of its return. A lot of women say that you have to accept that cancer will return. I did not want to live that way. 

Hearing a lecture on vitamin D gave me hope that I was doing something that was good, that was preventive. I couldn't make other changes (eating, exercise) - I was already doing those things. This was one of the things I could change that would make a difference. 

After my lumpectomy I did the full six weeks of radiation, but with a low oncotype I had no chemotherapy. I was on tamoxifen for almost 5 years, but finally came off due to side effects, which went away within three months of stopping the medication.

What is your vitamin D level?

My vitamin D level ranges from 50-60 ng/ml. I am currently cancer-free and I feel healthy. Fingers crossed!!

How do you get your vitamin D?

I take a minimum of 2,000 IU/day. If it is cloudy or cold I take more. I make an effort to be out every day for 20-30 minutes without sunscreen. If I think I am coming down with a cold I take 8,000 IU.

What would you recommend to others who are in a similar situation?

Do your research. Do your homework.

How do you tell others about vitamin D?

My whole family is currently getting tested regularly and takes vitamin D. I have taught them to know their numbers, and not just take the doctor's word for it that their vitamin D is "fine". 

One of the key pieces of evidence for my family was my husband (I guess my story wasn't enough...). After retirement he worked as a concierge of a water park. All the interaction with the public he would get cold after cold. I kept telling him to take vitamin D - since that helped me virtually eliminate colds. After 3 months of suffering he did - and since then he has rarely gotten sick.
How Much Vitamin D Should I Take?

How much vitamin D should I take?

Using data from our D*action project, we have created
D*calculator. With this calculator you can enter your current vitamin D serum level, your desired vitamin D serum level, and your weight. The calculator will tell you how much more vitamin D you need to achieve your desired serum level with both a 50% probability and a 90% probability. Give it a try!

How does it work?

GrassrootsHealth has analyzed the data of all of our D*action participants. We have plotted the dose response curve - a line plot of the average serum levels associated with each supplement dose. You will see that every dose has a wide range of serum levels - which is why we can't recommend a specific dose without first testing.

50% probability? 90% probability?

Using the data plotted in the chart, we calculated the average serum level for each supplement dose, as defined by the blue line. We also did a probability-based analysis to determine the supplement dose necessary to move 50% of the population from one serum level to another, and another supplement dose that would get 90% of the population across that same range. Of course the 90% number is substantially higher. 

Think of vitamin D levels like cholesterol levels

It would be much easier if there were a magic number that worked for everyone, but there isn't. Instead, think of your vitamin D level like your cholesterol - this will help you expertly manage it. 

Like cholesterol...  not everyone has the same level. You can't predict by height, weight, diet, or supplementation what your level will be. You need to test.

Like cholesterol...  if the test did not come back with your desired result you need to make a change.  For cholesterol that might be diet and exercise. For vitamin D it is likely to be more sun, supplements, or vitamin D rich foods.

Like cholesterol... you have to make the change consistently for a period of time, we recommend six months, and test again. See if your changes were effective. Do you need more? Less?

Calculate Now
Make a Difference Today - Join D*action Research

When we first started D*action many people could not get cost-effective vitamin D tests. Now, people use D*action because they...
  • want an independent test of vitamin D
  • want a test in the comfort of their home
  • don't have insurance
  • want to support GrassrootsHealth
We have a large number of participants (blue balls), but relatively few of our participants are regulars who test 1-2 times per year (the smiley face balls). While data from each and every participant is helpful and appreciated, our research becomes more robust with each return test and questionnaire. Additional tests over time also allow us to better analyze conditions that change over time (i.e. pain, cold, flus, falling, broken bones) and see how those conditions relate to changes in serum level.

We are offering a special now through March - a one-time test for under $50 ($48.75 plus $5 shipping)! 
This applies to current participants, subscribers, and even new participants. 

Your data has been presented to large audiences, published in journals, read by doctors world-wide. Here are some examples of how your vitamin D data has contributed to research and made a difference:
Editor's Letter
Susan Siljander
Marketing Director, GrassrootsHealth

It is easy to let life creep up on you and get behind. There have been times when I have been behind in testing my family for vitamin D. This month we are trying to give you a reason to catch up. We are offering a discounted rate that is lower than anywhere else on the Internet. 

Your test will make a difference. If every one of you re-enters D*action, even if you suspect you are sufficient, and gets one more friend to enter their data - we would double our database.

If everyone continues testing regularly for 2-5 more years, we could report on many conditions such as cold/flus. I suspect many of you have already lowered your colds through a vitamin D level greater than 40ng/ml. But I wonder... if we had all the data... for 10,000 people over 5 years... testing every 6 months... what would be the percentage reduction of cold/flus between a serum levels of 20 ng/ml (the general populace) and a serum level of 40 ng/ml (the D*action population average)? A 60% reduction? 80%? 90%?

I made a difference in December, by testing my whole family (assembly line style). When will you?

Thank you,

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.

Sign up to receive periodic educational text messages on your phone.


Calculate your estimated additional D intake to reach your target vitamin D serum level. (40-60 ng/ml recommended by our scientist panel).

Announcing new 1 hour CME by...

Dr. Michael Holick

Sunlight and Your Health: An EnLIGHTening Perspective.

Thanks to the sponsorhip of KBD, Inc. manufacturer of SPERTI ultraviolet products for home use.

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 Wagner, et al.
A GrassrootsHealth paper
Medical University of South Carolina
Published online October 2015

Read Paper

25-Hydroxyvitamin D in the range of 20 to 100 ng/ml and Incidence of Kidney Stones
Stacie Nguyen et al.
A GrassrootsHealth paper
October 2013

Incidence rate of type 2 diabetes is >50% lower in GrassrootsHealth cohort with median serum 25-hydroxyvitamin D of 41 ng/ml than in NHANES cohort with median of 22 ng/ml

Sharon L. McDonnell, et al.
A GrassrootsHealth paper
July 2015

25(OH)D Serum Levels > 50 ng/ml May Provide Additional Reduction in Breast Cancer Risk

Sharon L. McDonnell et al.
A GrassrootsHealth poster

GrassrootsHealth in the News

Bio-Tech Pharmacal Leads the Way with Supplement Donations for GrassrootsHealth Translational Research
February 22, 2016

Natural Medicine and Healing Wellness Summit

How to feel younger, reverse disease and live better now!
Online event
March 14-21

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