Hey Sue,
Thank you for the wonderful feedback. It's a perfect tutorial on the pharmacokinetics of vitamin D3 and the 25(OH)D response to dose of vitamin D3.
Hope you and yours had a wonderful pain free Christmas and here's to a Happy New Year.
Good questions... I'll address the vitamin D3 dose first. When it comes to vitamin D3 requirements, the experts say a dose of 5,000 to 7,000 IU/day should result in 90% of the people taking it having a 25(OH)D serum concentration of at least 60 ng/mL.
Under perfect conditions, this same dose of vitamin D3 should keep 90% of CH'ers who respond to the anti-inflammatory regimen pain free... Unfortunately, we rarely encounter perfect conditions...
Our immune system's T-Cells are major consumers of 25(OH)D. The presence of viral, bacterial and allergy inducing antigens trigger T-Cells into rapid cell division resulting in an army of millions of Pac-Man-like white cell eating machines roaming around our body gobbling up the offending antigens.
The simple fact of life is we're exposed to these antigens all the time so our immune system is constantly responding. Where we CH'ers run into trouble is when we're exposed new strain or a massive inoculation of antigens not previously experienced...
This triggers an even more vigorous immune response that consumes even more 25(OH)D. When that happens, 25(OH)D levels will drop to the point where they're incapable of preventing CH... so we get hit!
As a side note, infections and allergies aren't the only source of inflammation... Trauma, surgery, broken bones also result in inflammation that triggers an immune response...
10,000 IU/day vitamin D3 results in 90% of the CH'ers taking it achieving a 25(OH)D serum concentration of at least 80 to 85 ng/mL, (200 to 212 nmol/L).
This buys us sufficient 25(OH)D reserves to fight off most viral and bacterial infections without compromising the CH preventative capacity. All this happens automatically with no symptoms of infection. In short, we never knew it happened.
However, when we do start experiencing symptoms of an infection like an upper or lower respiratory viral infection, i.e., a cold, flu or allergic reaction... our immune system has been overrun by a new strain of antigens so it goes into a major immune response that drains our 25(OH)D reserves... and we get hit.
This is why I suggest another 25(OH)D lab test, doubling the daily maintenance dose of vitamin D3 from 10,000 IU/day to 20,000 IU/day and to add a 50,000 IU loading dose once a week at the first symptom of a cold or the flu. It wouldn't hurt to bump the daily magnesium intake from 400 mg/day to 500 or 600 mg/day...
Maintain this dosing schedule with all the other supplements and vitamin D3 cofactors until the cold or flu symptoms have cleared completely. At that point drop back to the maintenance dose of 10,000 IU/day.
Serum calcium and PTH (Parathyroid Hormone). This gets a bit more complicated... but for starters, the lab results for your serum concentrations of calcium and PTH are right in the middle of their respective normal reference ranges... i.e., perfect with no signs of vitamin D3 intoxication...
The following graphic illustrates the relationship between serum calcium and PTH and the role they play in calcium homeostasis...
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When serum calcium is at the low end of its normal reference range, chemo receptors in the parathyroid glads detect the low serum calcium concentration and this triggers production of the parathyroid hormone, PTH elevating its serum concentration.
PTH in turn stimulates the kidneys to metabolize 25(OH)D produced by the liver, into 1,25(OH)2D3, the active hormonal metabolite of vitamin D3. The extra 1,25(OH)2D3 pulls addition calcium from the gut raising the serum calcium concentration which in turn lowers the production of PTH in the parathyroid.
The actual mechanism of action in metabolizing 25(OH)D into 1,25(OH)2D3 involves the enzyme 1-a-25-Hydroxilase which adds an [OH
-] radical to the 1-a-25 position on the 25(OH)D molecule...
Hope this answers the mail... Have a happy New Year.
V/R, Batch