At the recent American Stroke Association Conference in February, 2015, evidence was presented that demonstrated better recovery after a stroke if vitamin D levels were high. This is more evidence to proof that you should make sure your vitamin D levels have been checked and optimized.
The study was performed in Massachusetts and colleagues studied 96 patients who had suffered a stroke. They assessed their blood levels of vitamin D (25-hydroxyvitamin D) and evaluated their outcome. 
We have known for a long time that low vitamin D levels have been associated in the past with neurovascular injury, or damage to the major blood vessels supplying the brain, brainstem, and the upper spinal cord. This study gives further evidence of the beneficial effects of vitamin D on brain tissue.
Amazingly, stroke patients who had low vitamin D levels less than 30ng/ml showed two-times (twice) larger areas of dead tissue in the brain compared to patients with norm vitamin D levels greater than 30ng/ml. Moreover, for every 10 ng/ml reduction in vitamin D level, the chance for healthy recovery in the three months following stroke decreased by almost half, regardless of the patient’s age or initial stroke severity.
Another recent study involving over 700 men and women followed for up to 10 years showed a reduction in the incidence of stroke when serum levels of vitamin D were high. Thus, the risk of having a stroke can be significantly decreased by making sure you have adequate vitamin D in your body.
At TrueMD, we have always recommended that patients make sure their blood levels of vitamin D are optimized. We recommend that patients try to increase their levels to greater than 50 ng/ml due to multiple reasons, including a proven decreased risk of many cancers. Many studies have confirmed a reduction in breast cancer, , prostate cancer, pancreatic cancer, colon cancer, and others cancers by increasing vitamin D to optimal levels. In addition, vitamin D is beneficial for the eyes, the heart, and many other organ systems., 
The present study confirms the importance of vitamin D and brain health. If it can help stroke patients recover, it certainly can help everyone by preserving the health of the neurons in our brains. Checking for your vitamin D level is thus important, and if low, get on a supplement of vitamin D to ensure maintenance of proper levels.
 Muhib A Khan, Jiaying Zhang, Majaz Moonis, Richard Goddeau, Nils Henninger, et al. “Predictors of Outcome in Patients With Acute M2 Occlusion” [Abstract #W P107]. Presented at American Stroke Association’s International Stroke Conference 2015, 5 Feb. 2015.
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