Treating Autism: A Nutritional Approach

 In Pediatrics

Tolle Causam

Darin Ingels, ND, FAAEM

Autism, or Autism Spectrum Disorder (ASD), is a developmental disorder manifesting in the first 2 years of life and affecting communication and behavior; it often manifests as long-term learning disabilities and/or emotional difficulties. Although ASD can be a lifelong disorder, treatments and services can improve a person’s symptoms and ability to function. ASD usually affects the way children communicate, and is usually accompanied by physical comorbidities of immune, neuromotor, and digestive function. Most children with ASD have multiple food intolerances/sensitivities associated with compromised gut health.1 This process has a significant inflammatory component that is exacerbated or triggered by an unbalanced gut microbiome and an inability of the body to tolerate specific kinds of foods.

GI Health & Food Sensitivities

Supporting gut health is critical for those with ASD. Because the enteric nervous system interacts with the community of bacteria that keep the immune system functioning properly, gut health plays a major role in both mental and physical well-being. Diet alone has clearly demonstrated a beneficial effect on gut flora and overall immune health, and is thus particularly important for these patients.

Many investigators have observed that food sensitivities are a contributing factor in ASD.2 Avoidance of certain foods can improve behavior and overall health for those on the spectrum.3,4,5 A general rule is to avoid, or at least minimize, the consumption of packaged products or processed foods. While this is not always possible, caregivers should make it a habit to read labels carefully and to be prepared to make phone calls to manufacturers to get specific questions answered about what is contained in each product consumed.

Research suggests that food allergies or sensitivities may play a key role in many cases of autism. While only a small percentage of children with autism have true life-threatening allergies, many others have delayed reactions to foods, involving different immune mechanisms. One reason that children with autism may be more susceptible to food reactions is increased intestinal permeability (aka leaky gut). One study found that up to 43% of children with autism had intestinal hyperpermeability.6 Gut dysbiosis and inflammation are now thought to influence the neural basis of ASD via the microbiota-gut-brain axis.7

Perhaps the most popular dietary recommendation for children with autism is a gluten- and casein-free diet. A 2012 study of parents’ observations of their children with autism revealed that such a diet led to significant improvement in autistic behaviors, including less stereotypy (“stimming”), better socialization, improved bowel habits, and increased expressive language skills.4 A 2018 systematic review of the efficacy of a gluten- and casein free diet in ASD found that a certain subpopulation of children with autism experienced gains in language and social ability and had fewer adverse behaviors while following the diet, while other children with autism experienced no observable changes.5 At the same time, there were no serious side effects from following a gluten- and casein-free diet. Despite some conflicting results in the research, there is good clinical evidence that some children with autism benefit from following a gluten- and casein-free diet; hence, it is worth trying. There has also been no evidence of nutritional deficiencies while following this diet, so children are not at risk of becoming nutritionally depleted.

Nutritional Support

In addition to dietary management, nutritional supplements, such as a basic multivitamin, may be beneficial to children with autism. One small study found that supplementing with a multivitamin for 3 months improved sleep difficulties and gastrointestinal problems, as compared with a placebo.8 Many children with autism self-restrict themselves when eating and are consequently prone to nutritional deficiencies. Providing a multivitamin may help prevent this from occurring.

B Vitamins

Several studies have shown that supplementation with vitamin B6 (pyridoxine), alone or in combination with magnesium, can lead to significant improvements in alertness, communication, social interactions, and IQ, as well as fewer self-injurious behaviors and emotional outbursts.2 Most studies used large doses of vitamin B6 (30 mg/kg of body weight per day, up to 1000 mg per day). Magnesium was given in doses between 6-15 mg/kg of body weight per day, up to 1000 mg per day. Although it is unclear how vitamin B6 and magnesium work in children with autism, it is believed to modulate dopamine metabolism.9 High doses of vitamin B6 can be toxic above 400 mg per day and cause “stocking-glove” paresthesias, where one experiences numbness from the elbow to the tips of the fingers, and from the knees down to the toes. As a result, high B6 dosing should be conducted under the guidance of a qualified healthcare practitioner. Anyone taking more than 200 mg of vitamin B6 should be monitored for signs of neurotoxicity. High doses of magnesium can cause loose stools, so the dose should be decreased if this occurs.

Some children with autism have been shown to have cerebral folate deficiency (CFD), where they make antibodies against the receptor that transports folate across the blood-brain barrier. Folate is necessary for normal growth and development. Children with CFD can suffer from irritability, delayed cranial growth, mental retardation, seizures, poor coordination, and autism. One of the nutrients that can help bypass this problem is folinic acid, a metabolically active form of folic acid. In a 2018 study, children with autism and CFD were given 2 mg/kg body weight per day, up to 50 mg a day, of folinic acid for 12 weeks. Compared with subjects taking a placebo, the folinic acid group experienced significant improvements in verbal communication.10 Folinic acid is well tolerated, even at high doses, and may help autistic children make gains in expressive language.

Gastrointestinal Health

Many children with autism have gastrointestinal comorbidities, including poor digestion. Inadequate breakdown of proteins, fats, and especially carbohydrates,11 can lead to additional inflammation in the gut and increased gut permeability. Supplementing with digestive enzymes can help ensure that food is properly broken down to optimize absorption. In a study of 101 children with autism between the ages of 3 and 9 years, either digestive enzymes or placebo were administered with each meal. After 3 months of treatment, the children taking digestive enzymes had fewer gastrointestinal problems, better behavior, and fewer overall autistic traits, compared with those taking placebo.12 In contrast, an earlier RCT found no clinical improvements in autism symptoms among ASD children taking digestive enzymes compared to placebo for 6 months, although there were possible beneficial effects on food variety.13 Further research is therefore warranted to confirm the widely observed anecdotal evidence of improvement from digestive enzyme supplementation in autistic children. A high-quality digestive enzyme will contain a mix of enzymes to break down carbohydrates, proteins, and fats, and may include – in addition to amylases, proteases, and lipase – dipeptidyl peptidase IV (DPP-IV), to help break down gluten and casein.

Perhaps even more important is the now well-established connection between the gut and the brain. Disruptions in the normal gut flora can lead to inflammation in the brain, potentially triggering or exacerbating autistic behaviors. Evidence has demonstrated this mechanism, suggesting that taking probiotics may be a way to help prevent brain inflammation.7 In an open-label study, 30 children with autism were given a probiotic containing Lactobacillus acidophilus, L rhamnosus, and Bifidobacterium longum for 3 months.14 At the conclusion of the study, behavior scores (Autism Treatment Evaluation Checklist, or ATEC) and gastrointestinal symptoms had significantly improved.

Probiotics are safe and effective and may help alleviate neuropsychiatric symptoms associated with autism. Although further research is needed to determine which strains are optimal, many healthcare practitioners recommend giving at least 10 billion CFU of Lactobacillus and Bifidobacterium species, as these are commonly found in healthy children.

Essential Fatty Acids

Children with autism have lower concentrations of omega-3 fatty acids compared with neurotypical children.15 Many of the studies examining omega-3 fatty acid supplementation have not shown any benefit in terms of communication, irritability, or hyperactivity. However, these studies included few participants, used suboptimal doses, and only lasted a matter of weeks. According to other studies of omega-3 fatty acids, much higher doses are typically used, and for longer periods of time, to achieve full benefits. Since many children consume insufficient dietary omega-3 fatty acids – such as from cold-water fish, nuts, and seeds – a fish oil supplement is a good idea and has no known serious side effects.

Mitochondrial Health

Impaired mitochondrial function is a common defect seen in ASD.16 Mitochondria produce the energy necessary for normal growth and development in children, and regulate energy metabolism in both children and adults. Several nutrients have been shown to support mitochondrial function, including coenzyme Q10 (CoQ10) and L-carnitine. In a year-long randomized, controlled clinical trial of subjects with autism, supplementing with CoQ10 and/or L-carnitine led to improved cognition and speech and better energy.17 L-carnitine may be given up to 50 mg/kg body weight per day,18 and CoQ10 may be given in doses up to 100 mg per day.19 This “mito-cocktail” may be enhanced with vitamin B6 and magnesium, as they are both also involved in mitochondrial function and energy production.


Autism is a complex neuropsychiatric illness that is often accompanied by complex physical comorbidities. Goals of nutritional intervention include correcting underlying nutritional deficiencies and improving metabolic function. Given the safety of these nutritional therapies, they are reasonable to try in children with ASD, even when definitive clinical research evidence of efficacy is lacking. Preliminary evidence and mechanism-of-action studies indicate that these nutrients may improve cognition, language, motor function, and behavior.

Many parents report seeing positive changes in their children on a nutritional program, often even after just a few weeks. Particularly when using higher doses of nutrients, naturopathic or functional medicine guidance is recommended, in order to design an optimal regimen and monitor progress of the individual child.


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Image Copyright: <a href=’’>serrnovik / 123RF Stock Photo</a>

Darin Ingels, ND, FAAEM, is a respected leader in natural medicine, with more than 26 years of experience in the healthcare field. He is board-certified in Integrated Pediatrics and is a Fellow of the American Academy of Environmental Medicine. Dr Ingels has been published extensively and is the author of The Lyme Solution: A 5-Part Plan to Fight the Inflammatory Autoimmune Response and Beat Lyme Disease – a comprehensive natural approach to treating the disorder. He specializes in Lyme disease, autism, and chronic immune dysfunction. He uses diet, nutrients, herbs, homeopathy, and immunotherapy to help his patients achieve better health.

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