Tom- but we are missing a step here. the body keeps producing 1.25-d because the VDR's, with which the 1.25-d interacts to activate the immune system, are blocked. any study that you read that discusses the beneficial effect of vitamin d is actually talking about 1.25-d which is actually more of a hormone than a vitamin. think about it, its high in the body, but it does nothing... because the next stage of the process is cut off.