What to do about chronic vitamin D deficiency

I was just found to have low levels of Vitamin D for the third time in the last year and a half.  I've been having various symptoms during that time, including joint pain, eyes that are sensitive to light and generally a little poorer vision than before, and heartburn or acid reflux (though that symptom has improved a lot).  I received numerous tests for those symptoms, and the vitamin D deficiency was the only thing that the tests found.  The previous two times I tested low for vitamin D, my doctor had me take 50,000 units once a week, for 8 weeks the first time and 12 weeks the second time.  I never noticed any improvement in my symptoms after taking the vitamin D, though my vitamin D level improved to a normal level.  I take a multivitamin daily which contains vitamin D, and also drink orange juice fortified with vitamin D and calcium, but that hasn't seemed to prevent my vitamin D level from becoming low again after I stop taking the high doses of vitamin D.

I was wondering if I should be taking a relatively high level of vitamin D all the time, rather than just for a couple months at a time.  Is it normal to have low levels of vitamin D even when you are getting some from a multivitamin and fortified juice, or might that indicate I'm not absorbing it well?  Also, since I never saw any improvement with my symptoms after taking high doses of vitamin D, could that be because my vitamin D level wasn't in the normal range for a long enough time for my symptoms to improve, or might that mean that the vitamin D deficiency isn't the actual cause of the symptoms?  Could the vitamin D deficiency itself be a symptom of whatever is causing the other symptoms, or is it more likely that it is the root cause of the problem?

[Paxiled]

Because we're being told to stay out of the sun, and work so much indoors, many people are now deficient in Vitamin D.  So yes, it's a good idea to take it as a regular supplement.  As it's fat soluble, it's best to take it with a meal that contains some fat.  As for recommended daily dosage, that's all over the map.

[EavlynnK]

I'm going to make the assumption that you have been put on vitamin D2. Am I right? There are two types of Vitamin D. There is D2 and there is D3. Vitamin D2 is synthetic and in turn the body struggles to absorb it, which is why it is given in such high levels. More  often than not, your levels will go right back down when you get off of it. Vitamin D3 is a natural form of D and is absorbed freely by the system. 5000 IU of D3 a day would bring your levels up, and 2000 IU a day would help you maintain. Food for thought, take it or leave it at will. Good luck to you!