Vitamin D Insufficiency Linked with Autism

Amy Taylor February 28, 2014

A new study by the Children’s Hospital Oakland Research Institute (CHORI) found that serotonin, oxytocin, and vasopressin – three hormones that influence social behaviour, are all activated by vitamin D hormone.

Autism, which is characterised by abnormal social behaviour, has previously been linked to low levels of serotonin in the brain and to low vitamin D levels, but no mechanism has linked the two until now.

In the study, researchers found that vitamin D hormone activates the gene that makes the enzyme tryptophan hydroxylase 2 (TPH2), which converts the essential amino acid tryptophan to serotonin in the brain. This suggests that adequate levels of vitamin D may be required to produce serotonin in the brain where it shapes the structure and wiring of the brain, acts as a neurotransmitter, and affects social behaviour.

They also found that vitamin D inhibits the production of enzyme tryptophan hydroxylase 1 (TPH1), which subsequently halts the production of serotonin in the gut and other tissues. Excessive levels of serotonin have been linked to inflammation.

According to the researchers, the new findings could help explain many of the known, but previously not understood facts: the “serotonin anomaly” or the low levels of serotonin in the brain and high levels in the blood of autistic children, the preponderance of male over female autistic children; oestrogen, a similar steroid hormone, can also boost the brain levels of serotonin in girls, the presence of autoimmune antibodies to the foetal brain in the mothers of autistic children: vitamin D regulates the production of regulatory T-cells via repression of TPH1.

The study suggests dietary intervention with vitamin D, tryptophan, and omega 3 fatty acids would boost brain serotonin concentrations and help prevent and possibly reduce some of the symptoms associated with ASD without side effects.

The best source of vitamin D is the sun, but it can also be obtained from food sources like fish, and multivitamin.

Source of this article:

Low Vitamin D Slows Serotonin Production, May Impact Autism