Is Autism a
Vitamin D-Deficiency Disorder?
Autism is increasing exponentially and is
related to vitamin D deficiency.
As I have pointed out in my
book, both children and adults with autism typically show
difficulties in verbal and non-verbal communication, social
interactions, and leisure or play activities.[1]
The cost of autism is about $35 billion annually, and the
societal cost for each case is about $3.2 million.[2]
The
most alarming increase in autism is observed over the past
few decades, and its incidence is currently growing at the
rate of 10-17% per year.39
Dr. John Cannell wrote a
compelling paper on how autism could be caused, at least in
part, by lack of vitamin D during brain development.[3]
Much
of this post discusses his primary arguments.
Cannell points out that in 1989, about the time autism began
its most rapid increase in incidence, the American Medical
Association Council on Scientific Affairs first warned of
the perceived dangers of sun exposure and advised keeping
infants out of the sun as much as possible.[4]
In 1999, when
autism risk began to really skyrocket, the American Academy
of Pediatrics advised to keep infants out of direct sunlight
and to make sure activities minimized sun exposure.[5]
In
2002 the Centers for Disease Control reported that the
efforts had been quite successful.5
It is quite possible that the result of all of this
"protection" has been an increase in autism, since the
increase in the incidence of autism has closely paralleled
the increase in "sunscare efforts."
Vitamin D is absolutely
essential for brain development[6] [7] and that children are
deficient because of sun "protection" measures that lower
vitamin D levels.
My opinion is that this is the major
reason for the surge in the rate of autism.
Here are more of Dr. Cannell's autism/vitamin D-deficiency
links:
Both autism and vitamin D deficiency are associated with
abnormally high inflammation.[8] [9]
Low consumption of vitamin D-rich seafood in pregnant women
correlates to increased risk of their children's low verbal
IQ's, poorer social performance, communication and motor
skills.[10] [11]
Dark-skinned people are far more likely to be vitamin D
deficient because they require more sun exposure to produce
it.
If the theory is correct, the rate of autism among black
children would be higher than that among white children due
to maternal vitamin D deficiency and fetal insufficiency
that would influence brain development.
This is exactly the
case; children of mothers who have emigrated from Uganda to
Sweden, for example, have an autism rate of 15%, which is
200 times that of the general population.[12]
Far less
sunlight is available in Sweden than Uganda, and the season
available for vitamin D production is much shorter in
Sweden.
This puts the Ugandan women at a severe disadvantage
in producing enough vitamin D for the developing fetus.
There is a close correlation between latitude and autism
among countries; the higher the latitude, the higher the
rate of autism.[13]
High-latitude countries have higher
rates of vitamin D deficiency due to a shorter season in
which UVB is available to stimulate its production in the
skin.
The same relationship of latitude to autism exists
within the states of the USA, with northern states having
higher rates of autism.[14] [15]
In winter, when vitamin D production is low, birth rates of
autistic children peak.[16]
Rickets and autism show similar urban/rural distribution
rates.
Rickets is an accepted vitamin D-deficiency disease,
and urban children have significantly higher rates of both
diseases.[17]
Pregnant rural women and their children tend
to be outside in the sunshine more their urban counterparts,
and in urban settings, more air pollution blocks out UVB
light, the wave length that stimulates vitamin D production;
poor air quality is directly correlated with autism[18] and
with profoundly lower serum levels of vitamin D.[19]
It is
also interesting to note that the Amish of
Pennsylvania mostly rural farmers have extremely low rates
of autism.[20]
According to Dr. Heng Wang, who treats Amish
people in rural Ohio, their rate of autism is 1 in 1,500,
compared to 1 in 166 nationally.[21]
Finally, where precipitation rates are high, rates of autism
are also high,[22] [23] suggesting a link with sunlight
deprivation. Cloudy, rainy weather blocks the UVB light
necessary to produce vitamin D.
The argument that autism is a vitamin D-deficiency disorder
is compelling, but until the theory is proven, it would
certainly be prudent to assure that pregnant women and young
children maintain optimal levels of vitamin D.
There is no
downside, and the potential to halt an unnecessary disease
that is devastating to youngsters, their parents and
society.
[1] Autism Society of America web site, accessed January 29,
2008
[2] Ganz, M. The lifetime distribution of the incremental
societal costs of autism. Arch Pediatr Adolesc Med
2007;161:343-39.
[3] Cannell, J. Autism and vitamin D. Med hypothesis
Oct 24, 2007. Epub ahead of print
[4] JAMA 1989;262:380-84. No authors listed
[5] Cannell, J. Vitamin D newsletter, May 2007.
[6] Eyles, D. et al. Vitamin D3 and brain development.
Neuroscience 2003;118:641-53.
[7] McGrath, J. et al. Vitamin D3-implications for brain
development J Steroid Biochem Mol Biol
2004;89-90:557-60.
[8] Ashwood, P. et al. The immune response in autism: a new
frontier for autism research. J Leukoc Biol 2006;80:1-15.
[9] Cantorna, M. . Vitamin D status, 1,25-dihydroxyvitamin
D3, and the immune system. Am J Clin Nutr. 2004
Dec;80:1717S-20S.
[10] Cantorna, M. . Vitamin D status, 1,25-dihydroxyvitamin
D3, and the immune system. Am J Clin Nutr. 2004
Dec;80:1717S-20S.
[11] Hibbeln, J. et al. Maternal seafood consumption in
pregnancy and neurodevelopmental outcomes in childhood (ALSPAC
study): an observational cohort study. Lancet. 2007
Feb 17;369(9561):578-85.
[12] Gillberg, C. Et al. Autism in immigrants: children born
in Sweden to mothers born in Uganda. J Intellect Disabil
Res. 1995;39:141-4.
[13] Grant, W. Epidemiological evidence for supporting the
role of maternal vitamin D deficiency as a significant risk
factor for the development of infantile autism in those born
prior to 1985. Unpublished manuscript.
[14] McNally, R. et al. An infectious aetiology for
childhood brain tumors? Evidence from space-time clustering
and seasonality analyses. Br J Cancer
2002;86:1070-77.
[15] Centers for Disease Control and Prevention. Prevalence
of autism spectrum disorders-autism and developmental
disabilities monitoring network, 14 sites, United States,
2002. MMWR Surveill Summ 2007;56:12-28.
[16] Stevens, M. Season of birth effects in autism. J
Clin Exp Neuropsychol 2000;22:399-407.
[17] Williams, J. et al. Systematic review of prevalence
studies of autism spectrum disorders. Arch Dis Child
2006;91:8-15.
[18] Windham, M. et al. Autism spectrum disorders in
relation to hazardous air pollutants in the San Francisco
Bay area. Environ Health Perspect 2006;114:1438-44.
[19] Agarwal, K. et al. The impact of atmospheric pollution
on vitamin D status of infants and toddlers in Delhi, India.
Arch Dis Child. 2002;87:111-13.
[20] Waldman M, et al. Does television cause autism?
National Bureau of Economic Research Working Paper 12632,
2006. http://www.econ.cudenver.edu/mocan/data%20for%20courses/Autism%5B1%5D.w12632.pdf
(accessed Feb 2, 2008.).
[21]Wang, H. Quoted by Dan Olmsted in The Age of Autism: One
in 15,000 Amish. UPI June 8, 2005. Available online at
http://pittsburgh.indymedia.org/news/2005/06/18948.php.
[22] Waldman M, et al. Does television cause autism?
National Bureau of Economic Research Working Paper 12632,
2006. http://www.econ.cudenver.edu/mocan/data%20for%20courses/Autism%5B1%5D.w12632.pdf
(accessed Feb 2, 2008.).
[23] Waldman,M. Autism prevalence and precipitation rates in
California, Oregon, and Washington counties. Arch
Pediatr Adolesc Med. 2008 Nov;162(11):1026-34
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