Posted by Larry Hoover on March 7, 2007, at 21:47:29
In reply to Re: Vitamin D deficiency, posted by natrfrk on March 7, 2007, at 17:46:12
> Thank you.
>
> I keep reading you should never take large doses of Vit D without taking calcium and magnesium. But you say it is safer NOT to. Can you help me understand?Let me go out on a limb and risk guessing you were diagnosed with secondary hyperparathyroidism? It's not important, but just guessing....
The biggest risk from increasing vitamin D intake as your doctor has prescribed would be from hypercalcemia (high blood calcium concentration). Vitamin D deficiency causes hypocalcemia (low calcium), but your body exerts considerable efforts to try and overcome the problem. That's what drives the parathyroid gland to produce large excesses of parathyroid hormone. With a sudden input of vitamin D into the system, there is a risk of tipping the balance far to the other direction. There are significant health consequences of excess circulating calcium. It is my belief that it is gentler on the system to allow vitamin D to do its job, and then make adjustments in diet only if at 12 weeks time the blood calcium levels are still too low. During this vitamin D deficiency period, your intestines have been unable to pump calcium out of the gut and into the blood. Upon restoration of normal vitamin D levels, the pumping efficiency will rise dramatically. You ought not to need extra calcium or magnesium to obtain normalized blood values.
Up until fairly recently, fears about vitamin D toxicity have led to significant under-estimation of optimal vitamin D intake. The old recommmendations of 200-400 IU per day fall far short of what we now know to be the levels which optimize dietary uptake....4,000 IU/day. I don't think very many people would even need to worry about calcium intake at 4,000 IU/day, although dietary magnesium intakes would still likely fall short, without supps.
BTW, your doctor's prescription of 50,000 IU/week is still below the no observed adverse effects level of 10,000 IU/day.
Here's a good summary article:
http://lpi.oregonstate.edu/infocenter/vitamins/vitaminD/Lar
poster:Larry Hoover
thread:739011
URL: http://www.dr-bob.org/babble/health/20070227/msgs/739087.html