New scientific research has suggested a potential link between lifelong dietary preferences for specific foods and autism spectrum disorder (ASD), with the connection possibly mediated by subtle effects on the immune system.
Genetic Data Reveals Dietary Patterns
Scientists from Shandong University Qilu Hospital in China conducted an analysis of genetic data, which can offer insights into people's long-term eating habits. This method allowed the team to investigate whether patterns of food consumption over a lifetime are associated with autism.
Out of nearly 200 foods examined, two items showed a notable correlation. Wholemeal pasta, which contains gluten, and cheese spread, rich in the milk protein casein, were both linked to a higher likelihood of autism in the analysis. Conversely, bananas showed the opposite pattern, with a higher inclination to eat them appearing to correlate with a lower likelihood of being autistic.
The researchers summarised their findings, stating: 'Our study suggests that the intake of wholemeal pasta and cheese spread is a risk factor for autism spectrum disorder.'
The Gut-Brain Connection and Immune Response
Autism is frequently accompanied by gastrointestinal issues like constipation, diarrhoea, and abdominal pain, leading to growing interest in the role of diet. The new study, published in the journal Frontiers in Nutrition, explored whether immune activity might explain the observed dietary links.
They found indications that cheese spread, in particular, was associated with changes in immune markers related to infection and inflammation, though the effects were described as small and complex. The researchers stress this does not mean eating or avoiding specific foods causes autism, or that diet can prevent it. Autism is a lifelong developmental condition present from birth.
In a second part of the study, the team reviewed records from 78 autistic children aged two to seven. With parental support, around half followed a gluten- and dairy-free diet for six months to a year, while the rest ate normally.
While there was no clear difference in standard autism symptom scores between the groups by the study's end, the children avoiding gluten and dairy showed a marked drop in immune antibodies linked to milk and wheat. The authors wrote that this shows 'adhering to a gluten-free, casein-free diet can effectively modulate food-specific immune responses.'
Experts Urge Caution Over Restrictive Diets
However, the researchers were clear to caution that this does not mean diet is a treatment for autism. In their paper, they stressed: 'Dietary modifications may help support the overall health of individuals with ASD but are not a direct treatment for ASD.'
Independent experts say such studies can help identify patterns but cannot prove that foods cause autism or that changing diet is an effective therapy. They also warn that restrictive diets can carry nutritional risks if not carefully managed, particularly for young children.
The study authors acknowledged the limits of their work, noting: 'Due to the relatively small sample size of the current study, further validation in large, multicentre studies is needed.'
According to the National Autistic Society, more than one in 100 people in the UK are on the autism spectrum, including around 700,000 adults and children. Autism affects how people communicate, interact and experience the world and is not an illness.
