This regimen is generally quite safe and well tolerated with many potential health benefits. However, some physicians and cluster headache patients may be concerned about the apparent “high” dose of vitamin D3. There are several studies that have clinically proven that the skin of a fair skinned adult clad in a bathing suit without sun block and exposed to the sun’s UVB at midday, can generate 10,000 – 15,000 I.U. vitamin D3 (cholecalciferol) in as little as 15 minutes.
Researchers at GrassRootsHealth, a public health promotion organization, recently published the results of their D*action Project where 3667 people have been taking vitamin D3 and having their 25(OH)D levels tested every 6 months since 2008. Participants also fill out questionnaires with each lab test in order to capture the essential demographic and epidemiological information.
439 of these D*action project participants reported taking vitamin D3 at doses up to and including 10,000 IU/day. 43 participants have had two or more consecutive tests for 25(OH)D while dosing on vitamin D3 at 10,000 IU/day. As you can see in the graph illustrated on the GrassrootsHealth home page shown below and used with their permission, none of the 3667 participants dosing at 10,000 IU/day or less had lab tests for 25(OH)D anywhere near the lower threshold for vitamin D3 intoxication at 200 ng/mL, (500 nmol/L).
2013-03-04