Vitamin A Supplementation for Autism Spectrum Disorder
Vitamin A supplementation is not recommended for improving symptoms of autism spectrum disorder based on current guideline evidence, which explicitly states that research does not support the efficacy of supplements or vitamins for ASD. 1
Guideline-Based Recommendations
The American Academy of Pediatrics practice pathway for autism spectrum disorders conducted a systematic literature review and reached a clear conclusion: the research evidence to date does not support the efficacy of other supplements or vitamins for treating symptoms in children with ASD. 1 This represents the highest quality guideline evidence available, published in Pediatrics in 2012, and directly addresses the use of vitamin supplementation in this population.
The 2014 American Academy of Dermatology guidelines similarly concluded that there is inconsistent to no evidence to recommend the use of multivitamin supplements, vitamin D, vitamin E, or vitamin B12 and B6 for treatment, though this was in the context of atopic dermatitis rather than core ASD symptoms. 1
Research Evidence on Vitamin A Specifically
While guidelines do not support vitamin supplementation, one pilot study from 2018 reported that vitamin A supplementation improved CARS scores and decreased serum 5-HT levels in children with ASD who had vitamin A deficiency. 2 However, this was a small pilot study without a control group, and this single positive study is insufficient to override the guideline consensus against vitamin supplementation. 1
Multiple systematic reviews from 2016-2019 examining various supplements for ASD consistently found little to no evidence supporting the effectiveness of dietary supplements, including vitamins, for improving core symptoms of autism. 3, 4, 5, 6
Clinical Approach
If vitamin A supplementation is being considered, it should only be used to correct documented vitamin A deficiency, not as a treatment for autism symptoms. 2 The rationale:
- Vitamin A deficiency can be assessed through serum retinol levels 2
- Supplementation should target nutritional deficiency correction, not behavioral symptom improvement 3, 4
- The evidence for symptom improvement remains insufficient despite one positive pilot study 3, 5, 2
Evidence-Based Alternatives
For managing symptoms in children with ASD, behavioral interventions have the strongest evidence base and should be the first-line approach. 1, 7, 8, 9 For specific issues like insomnia in ASD, melatonin has the strongest evidence base among pharmacological options, with effect sizes of 1.7 for reducing sleep onset latency. 1, 8, 9
Critical Pitfalls
- Do not use vitamin A supplementation as a primary treatment for core ASD symptoms based on guideline recommendations 1
- Do not assume that correcting nutritional deficiencies will improve behavioral symptoms, as the evidence does not support this connection 3, 5
- Avoid delaying evidence-based behavioral interventions in favor of unproven supplement therapies 1, 7, 8