December 10, 2015

Director's Letter 
Carole Baggerly 
Director, GrassrootsHealth 

Question:  How much should I take?

Answer: It depends.

Introducing... (drum roll)  


extremely basic, to allow you to use the published information from our research and, that of others, to give you some measurement guides! A present for YOU!

Let us know how it works for you!  Share, spread the word.

As a non-profit organization GrassrootsHealth has used the crowd-funding model to fund its initiatives. But this only pays for testing and data collection. To truly make an impact we need individual and business donors to help sponsor initiatives that will tip the scale in our direction. As we near the end of the year, please consider supporting GrassrootsHealth.


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

A Vitamin D Dosing Calculator

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.

Click to Expand

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?


Use this calculator for yourself, and pass along to curious friends. If you want to encourage your friends and family to test their vitamin D levels this holiday season, consider purchasing multiple test kits at a 40% discount using our D*advocate program.

Calculate Now
The Season of Giving

Moving Research into Practice, looking ahead to 2016

Why are we fundraising now? As we continue to gather data to analyze and publish, as we move forward with demonstration projects such as Protect our Children NOW!, funds from the test kits do not cover everything. Here are some examples of what extra donations could help to cover:
  • $ 3,000 - sponsors one paper to be published 'open access' so that everyone can read the full paper.
  • $ 5,000 - hosts one new CME video for a year - allowing doctors to learn about vitamin D as part of their continuing medical education.
  • $ 150,000 - starts one new Protect our Children NOW! initiative.
  • ANYTHING you wish to give is most appreciated!
Can you help?

If you want to donate toward these types of programs, click here. Also, you can give us contacts of companies who you think might want to sponsor one of these initiatives. If you have a contact you wish to share with us, please contact [email protected].

Donate Now
Editor's Letter 
Susan Siljander 
Marketing Director, GrassrootsHealth

The D*calculator is a great new tool to get people excited about vitamin D. And the best part is that they can't use it unless they know their current level - so it sparks a discussion about testing. I always find, after I convince someone to test their level, that their serum level and our Disease Incidence Prevention Chart is all they need to get on the right path. Usually they come back low - and you can describe to them the problems with being low. They check out the chart and... voila! They want to be within 40-60 ng/ml!

The D*advocate program will only be around until the end of the calendar year, so take advantage of getting 40% off your vitamin D tests--the lowest cost for home vitamin D testing on the Internet. You get a great price break on the tests and everyone who uses one of your gifts will add new data for D*action, strengthening GrassrootsHealth's position for research and education on vitamin D.

As we near the end of 2015, we can reflect back on the institutions that have added vitamin D to their standard of care. How many more will join the fold in 2016? 2017? This is made possible by your donations, your support through D*action, and your encouragement to others through programs like D*advocate

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.

D*advocate Program

Do you have a passion for vitamin D? Are you wondering what to give your friends and family? 

For $300 you will get:
  • Six vitamin D test kits
  • A letter you can customize for your recipients explaining the power of this gift
  • Six  5,000 IU bottles of Bio-Tech Pharmacal vitamin D

YOU can help solve the vitamin D deficiency epidemic by throwing a D*party!


Serum Level vs. Intake Chart
The chart off which the calculator is based.
Shows average changes in serum levels with additional supplementation

View Chart 

Letter to Veugelers, P.J. and Ekwaru, J.P., A Statistical Error in the Estimation of the Recommended Dietary Allowance for Vitamin D 
Robert P. Heaney 
Cedric F. Garland 
Carole A. Baggerly Christine B. French Edward Gorham 
Read Letter

Vitamin D Supplement Doses and Serum 25-Hydroxyvitamin D in the Range Associated with Cancer Prevention
Cedric F. Garland Christine B. French 
Leo L. Baggerly 
Robert P. Heaney

Read Paper

25-Hydroxyvitamin D in the Range of 20 to 100 ng/mL and Incidence of Kidney Stones  
Stacie Nguyen, MPH  
Leo Baggerly, PhD  
Christine French, MS  
Robert P. Heaney, MD Edward D. Gorham, PhD 
Cedric F. Garland, DrPH

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