Zinc supplements could reduce the chance of a child developing autism, according to a controversial study.
Japanese researchers who took hair samples from nearly 2,000 diagnosed autistic children, aged from birth to three, found almost half of them had a zinc deficiency.
The team from the La Belle Vie Research Laboratory in Tokyo concluded that zinc deficiency could lead to autism.
They wrote in the journal Scientific Reports: “These findings suggest that infantile zinc deficiency may epigenetically contribute to the pathogenesis of autism and nutritional approach may yield a novel hope for its treatment and prevention.”
In their research, three-quarters of the children from whom samples were taken were male, and a quarter were female. This was not unrepresentative, as autistic spectrum disorders – the umbrella term for all types of autism – are known to affect boys more than girls.
However, scientists have attacked the study for jumping to conclusions by failing to compare zinc concentrations in children without autism.
Uta Frith, emeritus professor of cognitive development at University College London, said:
“To conclude this study we would need to see data about zinc levels in children who do not develop autism spectrum disorders at different ages.
“Without this information, we cannot say whether zinc deficiency is associated with the development of autism spectrum disorders, let alone whether it is a contributory cause.”
Dorothy Bishop, professor of developmental neuropsychology at Oxford University, said:
“This study is problematic because the researchers assessed zinc levels only in an autistic group, relying on existing datasets to provide the data on expected normal ranges for zinc in children.
“To be convincing, they should have compared zinc levels in the hair of children with autism with levels for a control group matched in age and environmental background, with the measures being made by researchers who were unaware of the child’s group.
“Furthermore, if zinc deficiency is confirmed in future research, then it remains unclear whether this is a cause of autism or rather reflects dietary abnormalities.
“Many children with autism will eat only a restricted range of foods, and some have a habit of chewing inedible objects.”
Originally posted on The Telegraph.
