Fact Sheet - Gluten-free, casein-free diet

Cheeky young boy with spoon in mouth

Gluten-free, casein-free diet - extended version

What is the issue?

Many families try ‘alternative’ ways to help their child on the autism spectrum. One thing that some parents try is the ‘gluten free, casein free diet’. This means not eating food made from wheat (like bread, pasta and cake) or dairy (like milk, cheese and yoghurt). There has been a lot written about this kind of diet.

Why do people try this?

There are a few different ideas behind the diet. One is that these types of foods might not be broken down in the stomach properly and that some of the molecules can get from the stomach to the bloodstream. Some people think that this can have an effect on the way the brain functions.

What does the research say?

Research about this diet has found different results. There haven’t been many good quality studies about how the diet changes the behaviours of autism. Some studies have found that it is helpful, but the research had problems like low numbers of children in the study. Some well-designed studies have found few benefits.

A review article written in 2013 looked at a number of research studies over the last few years. This article reported that there were problems with the way a lot of the research was conducted. Some of the studies didn’t look at the effects of the diet. In about half the studies, the children were involved in other therapy so it is hard to know if it was definitely the diet that helped them. Most of the studies did not look at the impact on the families’ quality of life. This review said that at this stage, there is little scientific evidence to say that a gluten free, casein free diet is helpful for individuals on the spectrum.

In summary

High quality studies have not shown a link between the diet and an improvement in autism.

(Reviewed in November 2016)