We get excited every time there’s a new study that correlates vitamin D levels with any disease or medical condition. Each one gives us hope that the correlation will eventually be taken to the next level – an intervention study that uses rigorous random-trial experimental design to try to prove a causation, which is better than just a correlation. We want to know what vitamin D really can do, after all, even though we suspect it is critical to overall optimal health. Here are some of the latest correlations to hit the vitamin D scene:
Autoimmune Thyroid Disease
Over the course of four years in Seoul, Korea, 6,685 patients undergoing routine exams were additional examined for vitamin D levels and autoimmune thyroid disease. The rate of the disease was around 10% in the pool of patients examined, but women were nearly twice as likely to suffer from it than men. It was then discovered that vitamin D levels among those women with the disease were significantly lower than those without the disease. There was a significant correlation between vitamin D levels and the likelihood of the disease in pre-menopausal women, but not in post-menopausal women. Again, this is a correlation, so no causation should be inferred, but it points to the possibility that vitamin D has some kind of interaction with estrogen and the development of autoimmune thyroid disease.
In this study, researchers documented vitamin D levels for 286 patients with Parkinson’s Disease (PD) along with a range of cognitive functions and mood factors, including global cognitive function, verbal memory, fluency, function, executive function, disease severity, and depression. Scores on all of these items were higher with higher vitamin D levels, but only in patients who also did not suffer from dementia. Again, this is merely correlation, not causation. It’s possible that people with more advanced PD simply aren’t getting out as much in the sun and therefore have lower levels of vitamin D.
Actually, a link between vitamin D levels and autism is nothing new, but it’s possible that we’re getting closer to figure out the nature of the relationship. Here’s the path that seems to be emerging: Vitamin D plays a leading role in the brain synthesizing serotonin, and it may also play a role in making ht precursors to oxytocin and its receptor as well as vasopressin receptors. All of those are chemicals are neurotransmitters and hormones that play a role in, among other things, social behavior. The potential direct link is that lower levels of vitamin D may shut off the production of serotonin because its vitamin D that activates the gene that converts tryptophan into serotonin in the fetal brain. After birth, serotonin acts as a neurotransmitter that affects social behavior.
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