A review of gluten- and casein-free diets for treatment of autism: 2005–2015

Abstract

Background:

The gluten-free, casein-free (GFCF) diet is heralded by strong anecdotal parental reports to greatly improve and even “cure” symptoms of autism spectrum disorders (ASDs). Yet, to date, little conclusive empirical evidence exists supporting its use.

Objective:

The purpose of this paper is to provide an overview of the state of the recent evidence regarding the use of GFCF diet for treatment of individuals with ASD.

Methods:

Five database providers (PubMed, Web of Knowledge, EBSCO, ProQuest, and WorldCat) were used to search 19 databases, yielding a total of 491 articles that were published through February 2015. Peer-reviewed articles published between January 2005 and February 2015 were included for review if study participants were identified as having ASD and if the study investigated the effects of the GFCF diet on ASD behaviors or the relationship between the diet and these behaviors.

Results:

Evaluation of search results yielded eleven reviews, seven group experimental studies including five randomized controlled trials, five case reports, and four group observational studies published during the last 10 years. These studies represent a marked increase in the number of reported studies as well as increased scientific rigor in investigation of GFCF diets in ASD.

Conclusion:

While strong empirical support for the GFCF diet in ASD is currently lacking, studies point to the need for identifying subsets of individuals (eg, those with documented gastrointestinal abnormalities) who may be the best responders to the GFCF diet. Identifying these subsets is critically needed to enhance rigor in this research area. Until rigorous research supporting the use of GFCF diet is reported, clinicians should continue to use caution and consider several factors when advising regarding implementation of the GFCF diet for individuals with ASD.

Keywords::

• GFCF diet
• autism spectrum disorders
• review
• gluten free
• casein free
• dietary intervention

Acknowledgments

The authors acknowledge Caroline S Mikaiel for assistance with initial data analysis. This work was supported in part by the National Institutes of Health – National Center for Medical and Rehabilitation Research (NICHD) and the National Institute for Neurological Disorders and Stroke under grant number K12 HD055929. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Author contributions

JHE, CMK, and NMS contributed to the literature search. CMK, NMS, and MBD contributed to the data collection. All authors contributed toward data analysis, drafting and critically revising the paper, gave final approval of the version to be published, and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.