All children with autism spectrum disorder are different. A change in diet may help your child, but you’ll have to figure it out yourself.
We hear about miracle diets — but the truth is people vary, and the best diet is the one that works well for you. The idea that a special diet will help a child with autism spectrum disorder (ASD) does have some scientific backing. However the evidence is still early, and you’ll have to be especially careful to watch your child’s nutritional status.
The big picture
Research increasingly connects our gut microbiomes to mental health. Also, about half of people with ASD have gastrointestinal problems. GI symptoms are common in the general population, but there’s evidence that the frequency of GI symptoms in people with ASD matches up with the severity of ASD symptoms. For example, in an analysis of 960 children those with frequent bouts of abdominal pain, diarrhea, constipation, or gaseousness scored worse on social withdrawal, repetitive behaviors, irritability, and hyperactivity as measured by a well-known test, the Aberrant Behaviors Checklist. Even if your child didn’t have ASD, it’s worth putting effort to eliminate out certain foods to see whether you can relieve digestive symptoms.
Is your child hard to feed? As parents know well, children with ASD can be especially picky eaters. In a 2013 meta-analysis of studies to that point, researchers found that children with ASD are five times more likely to have tantrums at meals, engage in eating rituals, and reject food. They’re more likely to be malnourished, with shortages of calcium and protein in particular. Researchers are trying to address underlying anxiety, inflexibility, and sensory issues to expand food choices for children with autism.
The two most popular special diets for children with ASD require major changes in the standard U.S. diet. While parents often report that restrictive diets help, the diets can make it harder to keep your child well-nourished.
Gluten-free, casein-free diet
Early research with rats found that too much casomorphin, a morphine-like peptide fragment of the dairy protein milk casein, induced social isolation and apathy. One theory was that ASD was triggered when those peptides, released from casein and also gluten, cross a damaged intestinal lining and reach the central nervous system, affecting brain function. Some researchers have identified morphine-like compounds in the urine of people with autism and other neuropsychiatric disorders. More specific testing, however, does not support the idea that such disorders are related to gluten or casein.
A handful of small studies have tested whether children with ASD do better without eating casein and gluten. For example, in a randomized trial in Iran with 80 children, 54 percent had GI issues, and a gluten-free diet improved both the GI symptoms and behavioral problems. In a randomized, controlled yearlong study in Arizona, researchers compared 67 children and adults with ASD to 50 controls. The ASD volunteers took a special vitamin-mineral supplement, then received essential fatty acids, Epsom salt baths, carnitine, and digestive enzymes before they went on a gluten-free, casein-free, soy-free diet. The researchers reported improvements in IQ and autism symptoms from the diet and other interventions.
Low-carb Atkins-like diets produce ketones, a kind of fuel your liver produces when you’re low on glucose. Ketogenic diets (also known as keto diets) have been helpful for epilepsy in children and have seemed promising enough to test on ASD volunteers. In one 6-month study in Egypt, 45 children aged 3 to 8 were equally divided into three groups. One ate the ketogenic diet, another a gluten-free, casein-free diet, and the third were the controls. At the end of 6 months, both the diet groups showed improvement on autism symptoms, compared to the controls. But the ketogenic group did a bit better.
Should your child take supplements?
Nutrients in food are easier to absorb than nutrients from vitamin and mineral supplements.
If a child is on a special diet, has a poor appetite, and isn’t growing normally, you might speak to your pediatrician about nutritional supplements.
Overall, the evidence to date doesn’t suggest that any diet will dramatically improve things, but you might experiment with diet alongside other therapies. If nothing else, minimizing abdominal pain and other GI symptoms will make your child more comfortable.
March 18, 2021
Janet O’Dell, RN