Dose response equations for Vitamin D
Graph of Predicted vs. observed serum 25-hydroxyvitamin D concentrations.
serum vitamin D ng/ ml in blood = (427.46(1+pigmentation grade)10-2 +(dose IU/day)10-2)/Body massindex,
that is: (430 * square root of (1+pigmentation grade) + square root of IU)/ Body massindex
pigmentation grade: 2 = light, 1= intermediate, 0 = dark),
body mass index = (weight lbs)(703)/(height inches)**2
Equation does not consider other factors which will change change the response:
- medical problems, supplements, vitamin A, latitude, smoking, how much get from the sun (time in the sun, age, ...__
Equation appears to generally predict response correctly to within +-50%
Vitamin D dose-response is not linear – Feb 2011 equation up to perhaps 140 ng
Equation is based on data from 15-40 ng - doubt that this equation is correct for 60 ng
- from: Serum 25-Hydroxyvitamin D and the Incidence of Acute Viral Respiratory Tract Infections in Healthy Adults June 2010
[tiki-download_file.php?fileId=1204]
Based on 198 people in NE US in Fall and Winter 2009-2010

Close up view of the data

Need a vitamin D equation to account for:

Unhealthy people need even more vitamin D
And - the blood levels vary by 4X between individuals.
See also VitaminDWiki
4700 IU of vitamin D needed by most seniors – an equation -July 2014
200 IU needed to increase vitamin D levels by 1 ng (not 100 IU) – summary of 25 studies – Feb 2014 which has the following chart
