Vitamin D calculator and how to treat a low vitamin D level

First warning:
do not eat vitamin D supplements without medical advice and prescription.
Second warning:
do not eat products with added vitamin D but preferentially food naturally rich in vitamin D!
Third warning:
without measuring your vitamin D2 and D3 level it is difficult to optimize your status except if you have a very high solar exposition all over the year and no chronic disease.




http://www.vitdcalculator.com/

And on the App Store

How to treat a low vitamin D level?

We will not discuss here the rationale for supplementation. If you are advised by a physician to supplement you can follow those guidelines.

1/ if the blood level is under 30 ng/ml give a 200 000 UI vial of vitamin D by mouth and then 1000 UI per 11 kg (25 lbs) id est 7000 UI/d  for 80 kg of body weight. 8 weeks after doing the test.
2/ choose the level you want to achieve with supplementation, all other factors are supposed to be equal, depending on your starting level.
With this diagram determine the daily intake.

Serum 25(OH)D as a function of daily vitamin D intake, together with the best fit line to Eq. 1, its confidence limits, and the 95% probability band (outer dashed lines) for the entire cohort. For convenience in reading, the exponential constant and the coefficient of the linear term in the equation are in units of 1,000 IU/d. (Copyright Robert P. Heaney, 2011. Used with permission)

For instance: I have presently 32 ng/ml of vitamin D2 and D3 in my blood and I would like to obtain a 50 ng/ml level. I need an increase of 18 ng/ml. With 1000 UI/d I will have 8 ng/ml so I need at least 2250 UI/d, id est 67500 UI per month.

Plot of the regression line from Figure 2 on previously published high-dose data (8). Note that the horizontal axis is logarithmic. The diamond-shaped symbols are the means of controlled dosing studies (n=48) and the square symbols, individual values from reported cases (n=21) of vitamin D intoxication. (Copyright Robert P. Heaney, 2011. Used with permission)

And eventually, why do you measure vitamin D levels?

Plot of measured 25(OH)D concentrations against day of blood draw in the participants in study A. January 1 is assigned a day value of zero. The central curvilinear line is the least squares best fit of the data to a sine wave curve, and the outer lines reflect the 95% probability range of the data. To convert nmol/L to μg/L, multiply given values by 0.4. To convert kIU of vitamin D to μg, multiply given values by 25. 25(OH)D, 25-hydroxyvitamin D.

http://jn.nutrition.org/content/143/5/571.full


http://www.vitamindcouncil.org/

http://ar.iiarjournals.org/content/31/2/607.full.pdf+html