Everyone should check their Vitamin D level

April 22, 2015

Low vitamin D level predicts larger stroke size and poor outcome, according to a new study by University of Massachusetts researchers. They examined data on 96 consecutive patients with stroke and found a strong inverse correlation between the level of vitamin D and the size of the stroke. This is not surprising since vitamin D seems to be very important for the normal functioning of the nervous system. In a previous post I mentioned a study that showed an inverse correlation between vitamin D level and relapses of multiple sclerosis. Such correlation has been also found with migraine headaches and other major diseases.

Yes, all these studies are correlational and do not prove that taking vitamin D will prevent any of these conditions. But there is no evidence at all that taking vitamin D to maintain your blood level in the normal range has any side effects.

The stroke study was done only in caucasian patients and we know that blacks may need lower levels of vitamin D than caucasians, at least as measured by the standard blood test. This test is not very reliable since it measures the total level of vitamin D, while only the free portion of it is biologically active. To be safe, try to aim to have vitamin D level at least in the middle of normal range, which is from 30 to 100. Many people take the recommended 400 unit dose of vitamin D, but still have low levels in their blood. It is important to check your vitamin D level even if you are taking a supplement. Some patients require 2,000 and even 5,000 units daily to get their blood level to the middle of normal range.

Written by
Alexander Mauskop, MD
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