Diet and Autism

An interview with Brian Udell, MD.

Medically Reviewed by Louise Chang, MD on January 31, 2010
5 min read

Autism affects nearly one out of every 110 children, according to the CDC. That's more children diagnosed with autism than with diabetes, cancer, and AIDS combined. Yet a cure has yet to be found, and formal autism treatments are limited. So many parents are trying autism diets and supplements they've heard about from other parents or the media.

But can a child's diet really have an effect on autism or other autism spectrum disorders (ASD)? And which nutrients or foods offer promise to improve behavior, encourage children to be more communicative, or relieve the gastrointestinal conditions that often accompany autism?

WebMD turned to autism and learning disorder specialist Brian Udell, MD, director of the Child Development Center of America, for answers.

The most common GI symptoms include chronic diarrhea, abdominal distention, discomfort and bloating, gastroesophogeal reflux disease (GERD), excessive gas, constipation, fecal impaction, food regurgitation, and a leaky gut syndrome. Children with autism are also at risk for many other nutritional problems such as nutrient deficiencies, food allergies, food intolerances, and feeding problems.

First, there are no cures for the disorder and there is no one single best treatment for all children with ASDs. Every child must be evaluated individually. This can be tricky because the diagnosis usually occurs in 1- to 3-year-olds who are not great communicators. Doctors base their treatment protocols on lab results, parent reports, and physical exams. Even though there are no lab tests to diagnose autism, there are tests that can help us manage underlying symptoms.

Most children show improvement with early-intervention treatment services, where they learn important skills like walking, talking, and interacting with other children.

Depending on the symptoms, [many] kids are treated with some form of diet. Medication is common, as are physical, occupational, social, educational, and communication therapy. And because the research lags behind, some physicians try complementary and alternative medicine approaches that are safe.

According to the Autism Network, nearly one in five children with autism are on a special diet. There is no specific ASD diet, but removing certain proteins may relieve symptoms. The gluten-free, casein-free (GFCF) diet has the most research and is one of the most common dietary interventions. About 25% of my patients find relief and improvement with this diet. It excludes gluten, the protein in wheat, and casein, the protein in milk. In theory, kids improve on the diet because incomplete breakdown of these proteins create a ... substance that can inflame the gut. Studies have shown improvement and parents anecdotally report success when these two proteins are removed from the diet.

Parents can also have their children tested for celiac disease, which responds to a gluten-free diet.

Although a recent report in the Journal of Pediatrics suggests no need for dietary intervention, every parent needs to take a hard look at their child's diet. And if eliminating a few substances can put an end to the chronic diarrhea or make kids more communicative, most parents are willing to give it a try.

The first step for parents to try is an elimination diet for about a month to see if the omission of casein and gluten or other highly allergic foods, such as eggs, fish, seafood, tree nuts, peanuts, soy, and eggs, can improve symptoms. If the child is drinking lots of milk, I suggest starting with the elimination of dairy and replacing it with calcium-fortified soy or almond milk.

Elimination is a better barometer than testing for these allergic foods, since allergy testing may not be as effective.

After the elimination period, slowly introduce one new food at a time every few days. Keep a symptom diary throughout the elimination and reintroduction periods to determine which foods are tolerated.

These dietary changes may not be easy to implement, but they are non-invasive, no-harm approaches that are worth trying to see if your child improves.

Autistic kids who also have a seizure disorder may find relief from a high-fat, low-carbohydrate ketogenic diet. This diet often leads to poor growth, poor weight gain, and increased cholesterol levels, so it is imperative to use this approach under the supervision of a registered dietitian and physician.

Some children are successful when they follow a yeast- and sugar-free diet.

Most parents would benefit from tips and mealtime strategies to encourage their children to accept new foods. Parents need to serve as role models by eating the new foods that are introduced along with familiar foods.

Absolutely. Most kids with ASDs (or, for that matter, most kids) are picky eaters, go on food jags, and don't eat a well-balanced diet. Parents need to make sure their children are meeting their nutritional needs and a once-daily multivitamin with minerals is great insurance. Stay within accepted guidelines for all nutrients and make sure they are getting an adequate amount of all vitamins and minerals.

A healthy diet is essential for all kids, but even more so with kids with ASDs because there is concern their GI issues may lead to poor absorption of key nutrients for growth and development. One of our primary goals is to get kids eating a nutritionally complete diet and to reestablish a healthy GI system.

I recommend a healthy, natural, varied diet as close to the earth a possible. Avoiding pesticides, preservatives, artificial ingredients, fast foods, monosodium glutamate, or processed foods is ideal, but not always practical. Diets that are less processed and more natural, like an organic diet, are easier to digest and absorb because they contain fewer toxins that need to be eliminated.

Many of the kids with ASDs tend to be deficient in essential fatty acids, fiber, and protein. We turn to registered dietitians to evaluate diets and help parents understand where the nutrient gaps are and how to fill them.

I recommend omega-3 fatty acids because it is well known that these are "good fats" that can help reduce inflammation. Parents can try salmon, cod liver oil, or use mercury-free supplements.

Probiotics contain healthy bacteria and can improve the microflora in the GI tract. Kids with autism tend to have abnormal GI flora, and when they routinely ingest probiotics, their stools can improve. I suggest a probiotic with 1.5 to 4 billion bacterial colonies, depending on the age of the child. These are available in the grocery store.