Vitamin D and Autism

I was reading some information on Vitamin D today (our July 2008 Nutrient of the Month, by the way), and came across an interesting article entitled the Vitamin D Theory of Autism. It is an interesting read, and makes a strong case that the almost obsessive calls for virtually everybody (including pregnant women and children) to avoid sun exposure has contributed to the rise of autism. The only problem with this medical advice is that nobody bothered to mention that avoiding the sun causes the body’s Vitamin D levels to plummet. And the funny thing is, our ancestors didn’t avoid the sun like we do, and they didn’t have as much skin cancer (they were a little more wrinkled perhaps). And Vitamin D, a product of sunlight and hard to get from food, is necessary for proper brain development (among other things):

Yes, Professor John McGrath and Dr. Darryl Eyles of the University of Queensland in Australia have repeatedly warned us that normal brain development depends on adequate amounts of activated vitamin D to orchestrate the cellular architecture of the brain. Both the vitamin D receptor and the enzyme necessary to make activated vitamin D are present in a wide-variety of human brain tissues very early in pregnancy…

We do not know what vitamin D deficiency during pregnancy does to human brains, but we know what it does to rat brains and it is not good. In a series of recent animal experiments, Professor John McGrath, Dr. Darryl Eyles and their Australian group found severe maternal vitamin D deficiency in mother rats produced babies with abnormal apoptosis (normal cell death) and abnormal brain cell proliferation, reduced production of proteins involved in nerve structure, and baby rats who have subtle abnormalities in both learning and memory.

Because of this, researchers speculate that Vitamin D may help prevent autism, because it seems to explain just about every unexplained fact about autism:

The theory that vitamin D deficiency, during pregnancy or childhood, causes autism is just a theory. However, the theory has a plausible mechanism of action, explains all the unexplained facts about autism, subsumes several other theories, implies simple prevention, and is easily disprovable—all components of a useful theory.

Some researchers think that Vitamin D may even help improve the health of those with autism, although it cannot undo damage as a result of earlier deficiency. This will come as good news for parents of autistic kids:

If vitamin D was involved in autism, then symptoms might improve in the summer, when vitamin D levels are the highest. To the best of my knowledge, no controlled studies of such seasonality exist. A case study reported dramatic improvements in both sleep and behavioral problems in an autistic Japanese boy in the summer. Others reported significant improvements in autistic behaviors during a summer camp program that included swimming, hiking, boating, and other activities that would increase brain levels of activated vitamin D.

…However, if vitamin D is involved in autism then young autistic children, whose brains have not been irreparably damaged, may improve if they move to sunnier latitudes, increase their sun exposure, or start consuming more vitamin D in their diet. Consistent with the theory, not all children diagnosed with autism keep that diagnosis in adulthood and a few children either improve spontaneously or improve after one of the numerous treatment programs available. Naturally, any reports of improvement generate suspicion that the initial diagnosis was incorrect—an obvious possibility. A controlled 3-month study of 20 autistic children found that multivitamins with even low doses of vitamin D (150 units) improved symptoms compared to placebo. What would physiological doses of vitamin D do?

The article suggests pregnant women consider taking 2000 IU of Vitamin D per day (based upon a blood analysis of Vitamin D first). That is 5 times the RDA. One researcher concludes that in order to keep blood levels of Vitamin D normal, people need 3000 IU/day, which is much higher than the RDA, but is equivalent to what a fair-skinned person makes from being out in the sun for 3 minutes.

This is provocative reading, that is for sure, and it would be great if autism could be prevented (and helped) with a little sun exposure or a few pills. I highly recommend everybody read this article, and see what you think. Vitamin D is cheap. Even if you took 2,000 IU/day, it would cost about $13.00 per year from Puritan’s Pride. That is a heck of a lot cheaper than dealing with Autism after the fact (3.2 million per case over a lifetime).