Vitamin D research continues to amaze. The evidence mounts that vitamin D deficiency has a profound negative influence on the function of the brain. Previously, I wrote of the compelling evidence that autism is a vitamin D deficiency disease and also presented research indicative of a role of vitamin D in reducing depression, elevating mood and increasing happiness. Now, we see that in a small study of seventeen psychiatric patients, two were borderline deficient and 15 were deficient. Seven had such low levels that blood tests could not produce an accurate reading. Encouragingly, the researchers recommended that mental-health inpatients receive adequate exposure to sunlight.
In my book, I documented the critical importance of sunlight/vitamin D to the development and health of the brain:
1. Prenatal vitamin D deficiency in animals profoundly alters brain development.   Dr. Darryl Eyles and his colleagues state, “rats born to vitamin D(3)-deficient mothers had profound alterations in the brain at birth. The cortex was longer but not wider, the lateral ventricles were enlarged, the cortex was proportionally thinner and there was more cell proliferation throughout the brain… Our findings would suggest that low maternal vitamin D(3) has important ramifications for the developing brain."
2. Rats born to vitamin D-deficient mothers also have permanently damaged brains into adulthood and exhibit hyperlocomotion (excessive movement from place to place) at the age of ten weeks. Could this relate to hyperactivity in our children? Such rats also show impairment in learning and memory skills.
3. People hospitalized for bipolar disorder, and who are exposed to sunlight daily, are able to leave the hospital almost four days earlier than those who are not exposed,  and people hospitalized for seasonal affective disorder (SAD) also have shorter stays when they are placed in rooms on the sunny side of the hospital.
4. Two studies of mice with abnormal vitamin D receptors (VDR) in the brain found an increase in anxiety, aggression, poor grooming, maternal pup neglect and cannibalism.  Abnormal VDR cause a situation similar to vitamin D deficiency; the vitamin D that is available cannot properly stimulate the genes that prevent the anxiety, cannibalism, etc.
5. Another vital function of vitamin D is in inducing the production of nerve-growth factor (NGF), a protein that is essential for proper development of nerve cells in the brain and elsewhere.  It is obvious that if vitamin D is not present, nerve cells will simply not develop as they should in the central nervous system and brain, leading to the mental disorders we discuss here.
Can it be that the Powers of Darkness (the “sunscare” promoters) are partially responsible for the widespread depression, negativism, anxiety and psychological disorder that plague our society to a greater extent each year? Their efforts, coupled with modern indoor lifestyles, are leading to increases in a plethora of diseases, some of which are disorders of the brain. I believe it will be only a matter of time until vitamin D deficiency in pregnant women will be correlated to abnormally low IQ in the children they bear. In this blog, we have already discussed autism as a vitamin D deficiency disease, and there is an indication that women who conceive in the fall and winter tend to bear more dyslexic children, as well as children with other learning and reading disabilities.  The nervous system’s critical time to develop neural connections is in the first months after conception. If the pregnant woman is low in vitamin D during that time, it could affect the development of the fetal brain.
Activated vitamin D is a potent hormone that is essential for proper brain development. As a society and as parents, we cannot wait for more research before acting on the crying need for optimal vitamin D levels. Our mental and physical health, as well as that of our children, depends on it!
 Tiangga, E. et al. Psychiatric Bulletin 2008;32:390-93
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 Livingston, R. et al. Season of birth and neurodevelopmental disorders: summer birth is associated with dyslexia. J Am Acad Child Adolesc Psychiatry. 1993;32:612-6.
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