My vitamin d level has been very low & have taken 50, 000units twice a week for 2 1/2 years. current level is 8.4. what health issues could this cause?

Osteoporosis: Low vit d contributes to osteoporosis, but your levels are very low, inspite of taking excessively high doses, i would recommend seeing a physician to try to find out why you don't seem to be absorbing it.

Quite unusual: Agree with dr. Garnier. You are on a high dose and been on it for a very long time. If your level is still 8.4, you are not absorbing it and you need to know why. In the meantime, try vitamin d3 instead and go with different route: sublingual/drops and see if it will make a different. Good luck.

Low Vitamin D level: One reason vitamin d levels could be low when taking vitamin d supplements, is magnesium deficiency. Magnesium is required to convert vitamin d into its active form. Also, all the enzymes that metabolize vitamin d require magnesium as a cofactor. When you take large amounts of vit d but are magnesium deficient, magnesium has to come from cells -- more troubles! http://tinyurl.Com/msoth5j.