Diet & Autism (ASD)

Some children with Autistic Spectrum Disorder (ASD) or Asperger's Syndrome appear to experience food sensitivity to a wide range of foods and, in these children, dietary changes can result in improvements in associated behavioural and gastrointestinal(gut) symptoms.

There is no evidence to suggest that substances within the diet cause these problems in the first place, but rather they aggravate the underlying condition insusceptible children. These adverse responses to foods are often called food sensitivity, food chemical sensitivity or food intolerance.

Which foods?

There is a wide range of possible food substances that may have unwanted effects in children with autism including

Additive chemicals

  • colours
  • preservatives
  • flavours

To view the Official Shopper's Guide to Food Additives & Labels click here. 

Natural chemicals

  • Salicylates in many fruits, fruit juices & vegetables
  • Amines in foods such as chocolate, citrus fruits& mature cheeses
  • Glutamates in foods such as tomatoes, mushrooms & soy sauce

Whole foods such as wheat and milk.

There has recently been renewed interest in the possible adverse effect of wheat and milk, particularly in this group of children. Some research has indicatedthat gluten, found in wheat and other grain products, and casein, found in milk products have a role in the behaviours & symptoms seen in children with autism.

Gluten and casein are proteins which have a similar chemical structure, and when they are not adequately metabolised (broken down by the body) form substances called peptides. It is hypothesised that these peptides enter the bloodstream through a "leaky gut" and cross over to the brain where they affect brain function. Consequently gluten and casein free diets have been promoted for use in the management of autism.

But not all children with autism improve on gluten and casein-free diets. And there is also a lack of good scientific evidence to support the link between symptom improvement and removal of gluten and casein specifically, in those children who do show improvement when foods containing gluten and casein are excluded. Removal of foods containing gluten and casein is also likely to result in altered intake of other food chemicals so is is notclear ifthe improvements seen may be attributed to reducing the body load of these chemical in the diet rather than gluten and casein specifically. It is also unclear whether "leaky gut" exists in children with autism. This is an important area of investigation and large, good quality trials are needed to provide clearer answers.

In summary, for the best results it isimportant to consider a wide range of food substances,not just milk and wheat, when investigating food sensitivities in children with autism. Food sensitive individuals vary in their reactions to different foods and food chemicals, so there is no simple diet that suits everyone.

Which children?

Although it is not yet possible to predict the likelihood that food sensitivity is aggravating the underlying condition in a particular individual with autism or Asperger's, there is some evidence that a child is more susceptible to food sensitivity if

  • There is a history of allergies in the child or immediate family
  • There is eczema, migraine, or irritable bowel syndrome present in the child or immediate family
  • The parent/s can give a specific example of food causing a definite change in symptoms or behaviour of their child at some time

Some children without this history will also benefit from dietary investigation

Food sensitivity is not always obvious

Most parents are unaware that food is playing an aggravating role in their child’s condition for the following reasons

  • Children with food sensitivities often have a number of food substances causing problems
  • If the offending foods or drinks are consumed frequently the symptoms or behaviours can appear to be chronic
  • Food sensitivity reactions often do not occur immediately and can occur until up to 72 hours after eating the food or foods
  • Each child has his or her own threshold of tolerance forvarious food substances and so may not react every time the food is eaten.

All these factors make identification of specific food triggers difficult for parents.

Fussy Eaters

Many children with ASD are fussy, restrictive eaters and this may be exacerbated by undiagnosed food sensitivities.Once the offending foods have been  identified and excluded from the diet,some children experience improved eating habits and accept a wider range of foods.

Not all children with autism have food sensitivities, and the fussy, restrictive eating may be linked more to other issues such asdevelopmental delays in progression through to managing changes in food tastes, textures, colours and temperature.

Restrictive eating can affect nutritional intake so it is important to consult the dietitian for nutritional assessment and advice on strategies to encourage a greater variety of food. Some guided changes can make a difference over time.

For more information on Fussy Eaters click here .

For recommended online resources & products click here.

Where to start

A good starting point is to limit junk foods and packaged foods which means more food prepared at home. But for the best results it isnecessary to consider a wide range of food substances,including milk and wheat, when investigating food sensitivity in children with autism or Asperger's Syndrome.

All children respond differently, so it is essential to identify the specific dietary triggers for your child, to avoid unnecessarily over-restrictive diets. Food sensitive individuals vary in their reactions to different foods and food chemicals, regardless of their presenting issues, so there is no simple diet that suits everyone.

It is important to seek professional advice before making any major changes to your child’s diet as prolonged restrictive diets can lead to problems with nutrition. For the best results it is necessary to consider a wide range of food substances through a comprehensive food sensitivity investigation program. This is best done with the help of a dietitian experienced in this area.

For more on the Food Sensitivity Assessment Program click here.

 To make an appointment with the Dietitian please click here.