Gluten-Free, Casein-Free Diet and Autism Ranking:

Future Research

Summary of Existing Research

There is some research to suggest that some autistic individuals may have significant gastrointestinal problems, although the actual number of individuals with GI problems is unclear. There is no scientific consensus on whether autistic individuals do or do not have unusual levels of peptides in their bodies. 

Determining if gastrointestinal problems or high levels of peptides cause the core features of autism or related problems is not currently possible. We must wait until further research of sufficiently high quality has been completed. 

There have been several randomised controlled trials and several single-case design studies into the use of the gluten-free, casein-free diet for autistic people but the results are mixed.

Determining if the GFCF diet has any significant benefits for autistic individuals is not currently possible. We must wait until further research of sufficiently high quality has been completed.

Recommendations for Future Research

Future studies should 

• Use more scientifically robust, experimental methodologies with larger numbers of participants.
• Provide more details about the participants (such as whether they have a formal diagnosis of autism and whether they have any significant comorbidities, such as gastrointestinal problems).
• Investigate if there are different subsets of autistic individuals (such as those with high peptide levels, those with gastrointestinal problems or those with allergies to gluten and/or casein) who benefit most from the diet.
• Provide more details about the diet and how well the participants stick to it.
• Compare the gluten free, casein-free diet with other interventions which are designed to achieve similar results, such as a low sugar diet.
• Investigate the long term effects (more than one year) of excluding gluten and/or casein in the participants.
• Involve autistic people in the design, development and evaluation of those studies.

Updated

16 Jun 2022

Last Review

01 Aug 2017

Next Review

01 Nov 2023