Autism spectrum disorder (ASD) has been on the rise globally for decades, a pattern that may be explained by greater awareness, better detection methods, a widening definition, and / or an actual increase in the incidence.
While both genetic and environmental risk factors have been researched extensively, potentially modifiable risk factors such as metabolic syndrome and insufficient folic acid and vitamin D have not been studied in detail.
Recent studies have presented hypotheses on the mechanism behind the link between autism and deficiencies in vitamin D and folic acid, due to the increasing prevalence of autism coinciding with a marked enhancement in maternal folate status.
Additionally, more studies have implied that insufficient vitamin D in utero or in early life may be a risk factor.
Nutrients for neurodevelopment
Based on this, a researcher at Palestine's An-Najah National University conducted an analytical review of literature connecting micronutrient deficiencies to neurodevelopmental disorders to determine if the low nutritional status of Palestinian mothers and children was a risk factor for such disorders.
He used the latest Palestinian Micronutrient Survey as a reference for the nutritional status among the population: it had reported a prevalence of severe anaemia due to folic acid, iron, zinc and vitamin B12 deficiencies, with a third of pregnant Palestinian women suffering from the condition.
Furthermore, 87.1% of lactating mothers in the Gaza Strip and 78.2% in the West Bank were found to be zinc-deficient. When it came to children aged six months to five years old, a quarter of the boys and a fifth of the girls were considered anaemic.
Similar statistics regarding deficiencies in vitamins A, D and E, as well as folic acid, were noted.
This was despite Palestine's Ministry of Health having included nutrition in primary healthcare and public health programmes.
Women are given pre- and post-natal folic acid tablets, as well as iron tablets three months after conception and three months after birth. Newborns are given vitamin A and D drops until they are one year old.
Since 2006, Palestine has also had a public nutrition programme in the form of flour fortification in place, entailing the addition of 10 micronutrients to flour: folic acid, iron, niacin acid, zinc, and vitamins A, B1, B2, B6, B12 and D.
A puzzling predicament
According to the studies reviewed, maternal micronutrient status before and during pregnancy, as well as during lactation, is essential for healthy neurodevelopment in offspring. The first two years of life are particularly important, as a child's ability to build healthy immune and nervous systems are established during this time.
It was therefore possible that poor diet affected the health of both the mothers and children surveyed, as the studies also reported that diet had a prominent role in the manifestation of anaemia and vitamin D and E deficiency.
The researcher concluded: "It is still not clear whether nutritional interventions, and in particular micronutrient supplements (to mother or baby), could reduce the risk of neurodevelopmental disorders by enhancing the early development of the immune system.
"More future studies are needed to elucidate this relationship, which may contribute to a better understanding of preventative mechanisms."
Source: SAGE Journals
"Could Autism Be Associated With Nutritional Status in the Palestinian population? The Outcomes of the Palestinian Micronutrient Survey"
Authors: Mohammad Altamimi