Top 5 Nutrient Deficiencies in Children with Autism (and How to Fix Them Naturally)
As a pediatric clinical nutritionist and mother of a child with autism, I’ve seen firsthand how powerful nutrition can be in supporting children on the spectrum. While every child is unique, one common thread I see over and over in my practice is this: many children with autism have underlying nutrient deficiencies that, when corrected, can significantly improve mood, behavior, focus, sleep, and even speech.
In this post, we’ll explore the top 5 nutrient deficiencies in children with autism, how they impact the brain and body, and natural ways you can help your child restore these nutrients through diet and smart supplementation.
Why Do Children with Autism Have Nutrient Deficiencies?
Children with autism are at increased risk for nutrient deficiencies due to several factors:
Picky eating and food aversions (common in autism-related sensory processing issues)
Digestive issues like leaky gut, inflammation, or low stomach acid
Poor nutrient absorption from gut imbalances
Methylation and detoxification issues (like MTHFR gene mutations)
Chronic inflammation and oxidative stress
This is why a whole-child, functional medicine approach to nutrition is so essential for kids on the spectrum. Addressing underlying deficiencies can lead to real, observable improvements in your child’s health and development.
1. Zinc Deficiency
Why it's important: Zinc is crucial for immune function, brain development, and regulating neurotransmitters like dopamine and GABA. It's also needed for appetite regulation, wound healing, and proper digestion.
How deficiency presents:
Picky eating or strong food preferences
Poor growth or weight gain
Sensory issues
Immune dysfunction (frequent illnesses)
Anxiety, hyperactivity, poor focus
Why it’s common in autism: Zinc is often depleted in children with autism due to poor intake and impaired absorption from gut inflammation. Additionally, heavy metal exposure (like lead or cadmium) can block zinc from being used effectively.
How to fix it naturally:
Food sources: Grass-fed beef, pumpkin seeds, lentils, quinoa, oysters, chickpeas
Supplements: Look for zinc picolinate or zinc citrate—easily absorbed forms. Doses typically range from 5–20 mg daily, depending on age and need.
Bonus tip: Zinc and copper should be balanced. Test levels when possible.
2. Magnesium Deficiency
Why it's important: Magnesium is known as the "calming mineral." It plays a role in over 300 biochemical reactions, including muscle function, sleep regulation, stress response, and energy production.
How deficiency presents:
Anxiety, irritability, or mood swings
Poor sleep or restless legs
Constipation
Hyperactivity
Sensory seeking behavior
Why it’s common in autism: Stress, poor gut absorption, and low intake from diet all contribute. Many children with ASD have higher magnesium needs due to nervous system dysregulation and poor detox capacity.
How to fix it naturally:
Food sources: Spinach, almonds, avocado, black beans, sunflower seeds, bananas
Supplements: Magnesium glycinate (best for calm and sleep), magnesium citrate (best for constipation)
Start with low doses (50–100 mg/day) and titrate up slowly as tolerated.
3. Vitamin D Deficiency
Why it's important: Vitamin D is not just a vitamin—it's a hormone that regulates immune health, inflammation, brain development, and gut integrity. It's also linked to dopamine regulation, which affects motivation and mood.
How deficiency presents:
Low mood or irritability
Poor immune function
Fatigue or low energy
Developmental delays
Poor calcium absorption and bone health
Why it’s common in autism: Limited sun exposure, picky eating, darker skin tone, and poor fat absorption can all contribute.
How to fix it naturally:
Food sources: Egg yolks, salmon, sardines, fortified dairy or plant milks
Sunshine: Aim for 15–30 minutes of direct sun exposure daily (arms and face)
Supplements: Use Vitamin D3 with K2 for better absorption and calcium regulation. Doses range from 1000-5000 IU daily depending on labs and sun exposure. Always test first when possible.
4. Vitamin B12 and Folate (Methylation Nutrients)
Why they’re important: B12 and folate are essential for methylation, a key biochemical pathway that supports detoxification, neurotransmitter production, and DNA repair. Many children with autism have mutations in the MTHFR gene, which impairs folate conversion.
How deficiency presents:
Delayed speech or language regression
Poor focus or attention
Low energy
Mood disorders
Poor detox (sensitivity to smells, chemicals)
Why it’s common in autism: Children with MTHFR mutations may not convert synthetic folic acid or standard B12 into usable forms. This makes them more vulnerable to deficiency, even if levels appear “normal” on basic labs.
How to fix it naturally:
Food sources: Grass-fed beef, eggs, leafy greens, liver, salmon, nutritional yeast
Supplements: Use methylated forms like methylcobalamin (B12) and methylfolate. Doses vary but often start low and are titrated based on response.
5. Omega-3 Fatty Acids (Especially DHA)
Why they're important: Omega-3s, particularly DHA, are critical for brain development, focus, memory, and reducing inflammation. They also help balance mood and support the gut-brain connection.
How deficiency presents:
Poor language development
Trouble focusing
Dry skin or eczema
Mood swings or irritability
Inflammatory symptoms
Why it’s common in autism: Many kids do not eat enough fatty fish or omega-rich foods, and plant-based omega-3s (like flax) are poorly converted to DHA. Additionally, children with gut issues may have trouble absorbing fats.
How to fix it naturally:
Food sources: Wild salmon, sardines, mackerel, walnuts, chia seeds
Supplements: Look for high-quality fish oil or algae-based DHA (for sensitive kids). Start with 300–600 mg DHA per day depending on age and need.
Tip: Avoid products with artificial flavors or additives that may aggravate sensitivities.
How to Know If Your Child Has Deficiencies
While some symptoms are clear, many nutrient deficiencies are subclinical, meaning they don’t show up on basic labs or present subtly. Here are your best options:
Comprehensive nutrient testing through a functional medicine lab (like SpectraCell, Genova, or Great Plains)
Hair mineral analysis for zinc, copper, magnesium
MTHFR genetic testing if methylation issues are suspected
Symptom-based evaluation with a trained pediatric nutritionist (like me!)
How to Start Improving Nutrient Intake Today
You don’t have to wait for labs to start helping your child. Here’s what you can do now:
✅ 1. Add in One Nutrient-Dense Food Per Day
Try rotating in grass-fed meats, seeds, wild fish, or leafy greens in a child-friendly way.
✅ 2. Choose Functional Smoothies
Use smoothies to "hide" avocado, greens, flaxseed, or protein powders rich in B12 and zinc.
✅ 3. Use Targeted Supplements Cautiously
Not all kids need every supplement. Start with food-first, then add 1–2 key nutrients with professional guidance.
✅ 4. Work with a Pediatric Functional Nutritionist
Personalized guidance is essential. You’ll avoid wasting money on the wrong supplements and get a custom plan based on your child’s biology and needs.
REFERENCES:
Adams, J. B., Audhya, T., McDonough-Means, S., Rubin, R. A., Quig, D., Geis, E., ... & Barnhouse, S. (2011). Nutritional and metabolic status of children with autism vs. neurotypical children, and the association with autism severity. Nutrition & Metabolism, 8(1), 34. https://doi.org/10.1186/1743-7075-8-34
Arastoo, A. A., Paknahad, Z., & Maracy, M. R. (2020). Dietary intake, growth status and gastrointestinal symptoms in children with autism spectrum disorder: A comparative study. Research in Autism Spectrum Disorders, 70, 101474. https://doi.org/10.1016/j.rasd.2019.101474
Crider, K. S., Bailey, L. B., & Berry, R. J. (2011). Folic acid food fortification—its history, effect, concerns, and future directions. Nutrients, 3(3), 370–384. https://doi.org/10.3390/nu3030370
Goyal, A., Basak, S., & Bhattacharya, A. (2019). Role of vitamin D in autism spectrum disorder: A review. Cureus, 11(10), e5304. https://doi.org/10.7759/cureus.5304
Mousavinejad, E., Khoshbakht, Y., & Parisi, G. (2022). Omega-3 fatty acids supplementation for children with autism spectrum disorders: A review. International Journal of Developmental Neuroscience, 82(1), 1–8. https://doi.org/10.1016/j.ijdevneu.2021.12.001
Rossignol, D. A., & Frye, R. E. (2014). Evidence linking oxidative stress, mitochondrial dysfunction, and inflammation in the brain of individuals with autism. Frontiers in Physiology, 5, 150. https://doi.org/10.3389/fphys.2014.00150
Yektaş, Ç., & Sözeri-Varma, G. (2020). Evaluation of serum zinc levels in children with autism spectrum disorders: A case-control study. The Journal of International Medical Research, 48(5), 1–8. https://doi.org/10.1177/0300060520922025
