These foods contain an acid that is linked to autism.
An acid commonly used in processed food is linked to the rise in autism, according to research.
Propionic Acid — known as PPA — is used to increase the shelf-life of packaged foods.
The acid helps to inhibit mould growth in cheese and bread — and is also used in other foods, such as juices and dried fruits.
However, when neural stem cells were exposed to the acid, key molecular changes occurred, the researchers found.
When eaten by a pregnant woman, these changes may inhibit the development of neurons in the unborn child.
The acid has also been found in the stools of children with autism.
Autistic children frequently suffer from gastrointestinal problems, such as irritable bowel syndrome.
Dr Saleh Naser, study co-author, said:
“Studies have shown a higher level of PPA in stool samples from children with autism and the gut microbiome in autistic children is different.
I wanted to know what the underlying cause was.”
For the study, neural stem cells were exposed to PPA, the acid used in food processing.
The results showed that the acid reduces the number of neurons produced.
The acid also increased the production of glial cells.
An excess of glial cells is linked to inflammation, which has also been found in autistic children.
The damage the acid causes could hamper neurons communicating with each other.
This could lead to the characteristic signs of autism, such as repetitive behaviours and problems interacting with other people.
Pregnant mothers who eat processed foods, therefore, may be increasing levels of PPA in their gut and passing on these to the unborn child.
This research is still at an early stage, and the next step is to test the acid on mice.
The authors write:
“This research is only the first step towards better understanding of Autism Spectrum Disorder.
But we have confidence we are on the right track to finally uncovering autism etiology.”
The study was published in the journal Scientific Reports (Abdelli et al., 2019).
