Gluten-Free/Casein-Free Diets for Autism

Medically Reviewed by Dan Brennan, MD on September 02, 2023
4 min read

Autism spectrum disorders (ASD) are developmental disorders that affect children by disrupting their ability to communicate and interact socially. To reduce a child's symptoms of an autism spectrum disorder, some parents try a gluten-free/casein-free diet.

Little research has been done, though, on the gluten-free/casein-free diet for autism. Consequently, many parents wonder whether this diet really does, in fact, make a difference in the symptoms of children with autism. Some also believe that children with autism restrict their own intake, because they prefer bland food like white bread. Thus the question becomes “Chicken or egg.” Is the gluten causing the autism, or, more likely, is the autism limiting the child’s variety of food intake?

A gluten-free/casein-free diet is also known as the GFCF diet. It is one of several alternative treatments for children with autism. When following this strict elimination diet, all foods containing gluten ( found in wheat, barley and rye) and casein ( found in milk and dairy products) are removed from the child's daily food intake.

Some parents of children with autism believe their children are allergic or sensitive to the components found in these foods. Some seek allergy testing for confirmation. Yet, even when no allergy is confirmed, many parents of autistic children still choose to offer the GFCF diet. Among the benefits they report are changes in speech and behavior.

The benefit of a gluten-free/casein-free diet is based on the theory that children with autism may have an allergy or high sensitivity to foods containing gluten or casein. Children with autism, according to the theory, process peptides and proteins in foods containing gluten and casein differently than other people do. Hypothetically, this difference in processing may exacerbate autistic symptoms. Some believe that the brain treats these proteins like false opiate-like chemicals. The reaction to these chemicals, they say, leads a child to act in a certain way. The idea behind the use of the diet is to reduce symptoms and improve social and cognitive behaviors and speech.

There may be some scientific merit to the reasoning behind a gluten-free/casein-free diet. Researchers have found abnormal levels of peptides in bodily fluids of some people who have symptoms of autism. Still, the effectiveness of a GFCF diet for autism has not been supported by medical research; in fact, a review of recent and past studies concluded there is a lack of scientific evidence to say whether this diet can be helpful or not.

Unfortunately, eliminating all sources of gluten and casein is so difficult that conducting randomized clinical trials in children may prove to be very difficult.

Gluten is a mix of various proteins found in the seeds of several grains such as barley, rye, and wheat. A huge number of foods contain gluten. Gluten provides structure or binding to baked products. While it's quite difficult to avoid gluten, many stores, particularly natural food stores, display foods in a gluten-free area of the store. Still, it's important to read nutrition labels to see if there are additives containing gluten.

When someone is on a gluten-free diet, most bread and grain products are forbidden. Therefore, it is important to make sure that the child (or other person) receives ample fiber, vitamins, and minerals. Supplementation can help make up for the lack of these nutrients when foods containing gluten are eliminated.

Casein is a protein found in dairy products and other foods containing dairy or lactose. Even foods proclaiming to be dairy-free or lactose-free contain casein. Because many soy products and imitation dairy products also contain casein, it's important to read labels carefully when following a strict casein free diet.

Because the GFCF diet for autism restricts dairy products, you'll need to make sure the child's diet has other good sources of calcium and vitamin D. Both are necessary for strong bones and teeth. Talk with your child's doctor about fortified foods and/or supplementation to avoid any nutritional deficiencies.

There are a large number of online retailers who specialize in food products for people following the GFCF diet. Some parents make GFCF food in large quantities and freeze portions for a later meal.

Before making the change to a GFCF diet, consult your child's doctor. It is important for kids to still get a balance of the necessary vitamins, protein, fats, and carbohydrates in order to support healthy growth and development. A licensed dietitian can educate you about the GFCF diet and help you tailor the diet to your child's health needs and taste preferences.

In addition, before starting a child with autism on a gluten-free/casein-free diet, beware the hidden sources of gluten. Gluten can be found in fried foods that are dusted in flour, and even in cosmetics and some medications. Whole foods such as fruits, vegetables, and nuts may be safe. But avoid using packaged mixes because there may be traces of foods containing gluten that are not listed on the nutrition label.

Some restaurants are now categorized as GFCF-friendly. If you are concerned, ask the manager or server to show you a list of ingredients used in the establishment to make sure its dishes are gluten- and casein-free. Vegetarian/vegan restaurants are accustomed to serving people on special diets and may be more willing to prepare dishes that adhere to the restrictions of a strict GFCF diet.