Differences in food consumption and nutritional intake between children with autism spectrum disorders and typically developing children: A meta-analysis.
Autistic kids reliably miss calcium, vitamin D, dairy and omega-3—check and supplement, no special diet required.
01Research in Context
What this study did
The team pooled 33 studies that weighed or logged what autistic and typical kids ate.
They compared daily intake of 20 nutrients and major food groups.
The final sample: 2,054 autistic children and 2,076 controls, .
What they found
Autistic kids took in less calcium, vitamin D, protein, dairy, and omega-3 fats.
They ate more fruit, vegetables, and vitamin E.
All gaps were small, but they showed up again and again across countries.
How this fits with other research
Çıtar Dazıroğlu et al. (2024) later added antioxidant capacity to the list and found the same shortfalls.
Öztürk et al. (2026) scoped gluten-free casein-free diets; their review covers the same kids Esteban-Figuerola et al. (2019) counted, so the low dairy finding is already baked into the GFCF evidence base.
Tonnsen et al. (2016) challenged kids with real gluten and casein snacks and saw no behavior spike. That null result sits beside Patricia’s low-dairy intake data: together they warn us that removing dairy is unlikely to change core symptoms, even if calcium stays low.
Why it matters
Low calcium and vitamin D can thin bones and worsen sleep. You can spot these risks in minutes with a 3-day food log. Add a chewable calcium-vitamin D supplement if dairy stays under two servings a day. No need to ban gluten or casein—just bridge the gap.
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02At a glance
03Original abstract
Children with autism spectrum disorders show higher food selectivity, which restricts consumption of some foods and may cause nutritional deficiencies. The aims of this meta-analysis are to determine the overall differences in nutritional intake and food consumption between children with autism spectrum disorder and control (typical development) children, as well as determine the extent to which the nutritional intake and food consumption of autistic children comply with the dietary recommendations. Children with autism spectrum disorder consume less protein (standardized mean difference = -0.27, 95% confidence interval (-0.45, -0.08)), calcium (-0.56 (-0.95, -0.16)), phosphorus (-0.23 (-0.41, -0.04)), selenium (-0.29 (-0.44, -0.13)), vitamin D (-0.34 (-0.57, -0.11)), thiamine (-0.17 (-0.29, -0.05)), riboflavin (-0.25 (-0.45, -0.05)) and vitamin B12 (-0.52 (-0.95, -0.09)) and more polyunsaturated fat acid (0.27 (0.11, 0.44)) and vitamin E (0.28 (0.03, 0.54)) than controls. Autistic children also consume less omega-3 (-0.83 (-1.53, -0.16)) and more fruit (0.35 (0.12, 0.59)) and vegetables (0.35 (0.09, 0.61)) than control children; however, these results must be considered with care due to the low number of studies included in the analysis and the high heterogeneity. The results also suggest a lower intake of calcium, vitamin D and dairy and a higher intake of fruit, vegetables, protein, phosphorus, selenium, thiamine, riboflavin and vitamin B12 than recommended.
Autism : the international journal of research and practice, 2019 · doi:10.1177/1362361318794179