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

Current Research

We have identified more than 20 scientific studies of the gluten-free, casein-free diet for autistic people published in English-language, peer-reviewed journals.

The published studies included a total of 200 plus individuals aged from 2 years old to adult with a variety of diagnoses including autism, autistic disorder and pervasive developmental disorder (not otherwise specified).

• The majority of the studies examined the gluten and casein-free diets together, sometimes compared with no treatment or placebo.
• One study (Nazni et al 2008) compared the gluten-free diet with the casein-free diet and with the gluten-free, casein-free diet.
• One study (Reichelt 1990) compared the gluten-free diet with a restricted gluten-free diet.
• Two studies (Bird et al 1977; Johnson et al. 2011) compared the gluten-free and/or casein-free diet to other interventions (a behavioural intervention; a low sugar diet). 
• One study (Lucarelli 1995) examined the removal of cow milk protein.
• The majority of the studies (16) reported significant improvements in areas such as the core symptoms of autism, gastrointestinal problems, and challenging behaviours
• One study reported mixed results and seven studies reported no significant improvements

Please note: we have not included any studies in which the gluten-free, casein-free diet was provided as part of a multi-component package alongside other treatments (such as chelation). Nor have we included any studies in which a wide range of foodstuffs (not just casein and gluten) were excluded at the same time. 

Updated

16 Jun 2022

Last Review

01 Aug 2017

Next Review

01 Nov 2023