There is an increasing amount of science that links lack of vitamin D to autism. In a new study, 109 autistic children were given either a vitamin D supplement or placebo. According to the lead researcher, Dr. Khaled Saad, there was a distinct improvement in autism symptoms such as hyperactivity, social reclusion, and other function impairments in the children who took supplements of vitamin D, but not in the placebo group. The study is published in the Journal of Child Psychology and Psychiatry (2016).
It is alarming that many babies are born with a vitamin D deficiency, or become vitamin D deficient later in life. The nutrient controls numerous processes in the brain – including gene control and regulation of serotonin (neurotransmitter) levels and inflammation processes.
What is autism?
There are different levels of autism, and the disease is characterized by a different and in many cases delayed development of lingual skills, communication, and social behavior. People with autism are often highly sensitive to sensory input, have phobic anxiety, throw tantrums, and may have self-destructive behavior. The number of people diagnosed with autism has increased rapidly over the past decades.
Known risk factors
- Environmental toxins – including heavy metals and chemicals
- Genetic predisposition
- Late parenthood (after the age 35 years)
- Complications during pregnancy and birth
- Overdiagnosing (ever since the criteria were changed in 1994)
- Lack of vitamin D
- Consumption of medicine that interferes with vitamin D during pregnancy (e.g. Valproate against epilepsy)
- Other risk factors exist, but there is a lot of evidence to suggest that lack of vitamin D is the common thread that influences both genetic and environmental factors.
|Leading scientists assume that our modern way of living and the many campaigns against skin cancer have made people fearful of the sun, giving rise to more widespread vitamin D deficiency. This may be a contributing factor in the increasing rate for autism.|
Link between vitamin D, sunshine, and autism
The sun is our primary source of vitamin D, a nutrient that has a multitude of functions in the body. Because of its important role in human health, a deficiency may have wide implications. In 2008, Dr. John Cannell pointed out that the rate of autism was higher in regions of the United States with more cloudy and rainy weather and in regions with less UVB radiation, which is typical of northern states and cities with a high level of air pollution. Also, people with darker skin are at increased risk of having too little vitamin D and developing autism.
Many, but not all, studies have shown a relation between autism and lower levels of vitamin D. The baby’s vitamin D levels at birth depend on the mother’s vitamin D status during her pregnancy. At northern latitudes, more babies with autism are born during spring where vitamin D levels are at their lowest. A Swedish study shows that children, who develop autism later in life, had lower vitamin D levels at birth compared with their siblings. Genetic factors may also play a role in terms of the child’s ability to utilize and activate vitamin D. However, we need more studies to get a clearer picture of this.
Mechanisms between vitamin D and autism
All brain cells have vitamin D receptors. Scientists estimate that vitamin D controls 5-10 percent of our genes. Autism is linked to environmental toxins and oxidative stress in the brain that may lead to inflammation, cell damage, DNA mutations, and cellular death. The scientific literature reveals that vitamin D can reduce oxidative stress and protect cells against DNA damage. Vitamin D also counteracts inflammatory processes by increasing the number of white blood cells (regulatory T cells) that decrease the immune response.
Least but not last, vitamin D controls serotonin levels in the brain.
Vitamin D, tryptophan, and serotonin
The two Ph.D. scientists, Rhonda Patrick and Bruce Ames, at the Children’s Hospital Oakland Research Institute (CHORI), have managed to identify the more specific interplay between vitamin D, serotonin, and autism. They found that vitamin D controls a gene that is responsible for converting the amino acid, tryptophan, into serotonin. Serotonin is known for its role as a brain neurotransmitter that influences mood, and anti-depressive medication also works by controlling serotonin levels in the brain. However, serotonin has many other functions in the brain and in the rest of the body.
Vitamin D controls serotonin in the intestine and the brain
People with autism often have elevated serotonin levels in their intestine and too little serotonin in their brains. Studies have showed that vitamin D has the potential to lower the serotonin production in the intestine and increase it in the brain by regulating certain genes.
Serotonin’s role in brain development
During pregnancy, serotonin plays an important role for the development of the child’s brain. If there is too little serotonin, it may have a negative effect on the structure of the brain and on brain functions. According to Rhonda Patrick, studies of mice have demonstrated that a lack of serotonin leads to autistic traits. She has also observed that the fetuses are completely dependent on the mother’s vitamin D status. During pregnancy, vitamin D is transferred from the mother via the placenta. Afterwards, vitamin D crosses the blood-brain barrier of the fetus so that genes can convert tryptophan to serotonin by means of enzyme processes. If the mother lacks vitamin D, it may therefore harm the brain development of the fetus.
Other studies with vitamin D and autistic children
In his last book from 2015, Dr. John Cannell describes two studies where scientists gave supplements of vitamin D to children with autism. In one study, 83 autistic children were supplemented with a high dosage (125 micrograms/5,000 IU) of vitamin D for three months. 67 of the children (80 percent) had substantial improvements with regard to stereotype behavior, eye contact, and attention.
Make sure to get enough vitamin D during pregnancy
Women who plan to become pregnant, and women who are already pregnant, should have their vitamin D status measured. They should also take a vitamin D supplement during the entire winter period in order to have optimal levels of the vitamin in their blood. Because the diet only contributes with minimal quantities of vitamin D, it is important to expose yourself to adequate amounts of (unprotected) sunshine during the summer but without getting a sunburn.
Vitamin D, supplements, and absorption
Vitamin D is lipid-soluble, which means that we obtain the best absorption and utilization of the vitamin if it is dissolved in oil in capsules. A daily intake of up to 100 micrograms of vitamin D is considered as safe. In the above-mentioned studies, however, the administered dosages were higher.
Khaled Sall et al. Randomized controlled trial of vitamin D supplementation in children with autism spectrum disorder. Journal of Child Psychology and Psychiatry. 2016
John J Cannell. Autism Causes, Prevention and Treatment: Vitamin D Deficiency and the Explosive Rise in Autism Spectrum Disorder. Sunrise River Press. 2015
R.P. Patrick, B.N. Ames. Vitamin D hormones regulates serotonin synthesis. The FASEB Journal 2014
Science News. Causal link found between vitamin D, serotonin synthesis and autism in new study. Science Daily. 2014
Rhonda P. Patrick and Bruce Ames. Vitamin D and the omega-3 fatty acids control serotonin synthesis and action, part 2: relevance for ADHD, bipolar schizophrenia, and impulsive behavior. The FASEB Journal 2015.
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