Children with autism often struggle with food. Perhaps your child has an extreme preference for one type of food, extreme avoidance of another, or rituals around eating and mealtimes that become disruptive.

Behavior therapy can help to mitigate these issues. Most doctors recommend behavior therapy as the primary approach to understanding and managing autism symptoms.

In some cases, your child’s food preferences may be based on “fragile gut,” a common comorbidity of digestive issues that many people with autism share. Foods that exacerbate discomfort in the gut might trigger certain behaviors around food or meals.

Many parents now look for supportive diets to help their children. Currently, many are turning to gluten-free, dairy-free, and ketogenic diets. There is some scientific evidence that these diets are supportive for children with autism, but the research is still new.

It’s important to work with your child’s pediatrician and a nutritional therapist to understand the full extent of these diets. By teaching you what your child should eat and what they should avoid, these professionals can ensure that your child gets enough nutrients to support their long-term development.

Autism’s Effects

Autism spectrum disorder (ASD) is a developmental disability that changes how an individual communicates, learns, and socializes.

The main approach to managing symptoms of autism is behavior therapy, most often applied behavior analysis (ABA) therapy. A board certified behavior analyst (BCBA) creates a tailored treatment plan for each client, sets specific smaller goals within the larger treatment goal, and measures outcomes to assess the effectiveness of treatment. Registered behavior technicians (RBTs) usually implement this care plan directly with clients, while the BCBA supervises the entire treatment process.

People with autism have other deficits that require additional types of therapies, including physical therapy, occupational therapy, and talk therapy. They may benefit from complementary therapies like art therapy or music therapy.

Today, nutritional therapists are offering supportive therapies for people with autism as a way to manage physical ailments, mood, and behavior.

Ensuring Children With Autism Eat a Healthy Diet 

Nutritional therapy — which might include eating or avoiding specific foods, taking vitamin supplements, or focusing on a certain dietary plan — is a new approach to addressing some symptoms of autism.

Specific diets and nutritional therapy could be potential complementary treatments for autism, rather than the main form of treatment. They should never be used to replace a primary form of autism treatment, like ABA therapy.

According to the Centers for Disease Control and Prevention (CDC), a review in 2017 of 19 different dietary studies on the effects of different diets for children with autism did not find enough scientific support for this approach. Ultimately, there wasn’t enough evidence to conclude that diet could effectively manage autism symptoms.

Despite this conclusion, children on the autism spectrum have a range of needs. Nutritional support may be beneficial for some children or adults with autism.

Supporting Healthy Eating & Development in Children With Autism 

There are different stages at which nutrition may impact a child with autism. Ongoing research is clarifying when certain developmental disorders arise, so what we know is still evolving.

It is believed that a combination of underlying causes may potentially impact the severity of a child’s autism symptoms and how they can be managed throughout life.

  • During pregnancy: Research has shown that brain development begins as early as 18 days after conception. Processes that interfere with brain development can lead to developmental disorders in infants. While autism has not been tied to a specific problem in utero, a genetic condition, or an environmental substance, studies have shown that suboptimal nutrition during pregnancy can affect behavior and cognition throughout the child’s life. Brain development during the third trimester appears to be especially vulnerable to nutritional deficiencies. Managing diet to avoid some potentially harmful foods, while boosting intake of vitamins and minerals through other foods, can be an important way to manage your child’s healthy development during pregnancy.
  • During growth: People with autism often have food aversions or sensitivities. This can lead to them regularly choosing certain foods and avoiding other foods. It can also lead to some nutritional deficiencies, especially in children. While forcing a child to eat a food they hate does not generally work, adding dietary supplements to the overall nutritional plan or choosing other foods with similar nutritional content may work. You can get a referral to a nutritional therapist through your pediatrician, to help your child get the right combination of nutrients. A study conducted at Emory University School of Medicine found, in a meta-analysis, that children on the autism spectrum were five times more likely to have behavioral challenges around mealtimes, including ritualistic eating behaviors, extreme selectivity with certain foods, and even tantrums over food options. The study also found that children with autism were more likely to have nutritional deficiencies compared to their neurotypical peers. Calcium and protein, in particular, were lacking in the diets of many children with autism. In extreme scenarios, these deficiencies can lead to stunted growth, bone problems, muscle issues, and trouble with cognition.
  • Throughout life: Dietary problems that start in childhood can increase the risk of diseases like diabetes and cardiovascular disease later in life. These chronic conditions have a hereditary component, but they are also closely associated with dietary problems and obesity. Starting your child with a healthy diet can allow them to learn to manage their own eating and health later. This can help them to avoid chronic illnesses that require additional medical treatment.

How Children With Autism Experience Food Differently

People on the autism spectrum often display strong food preferences and avoidances, particularly as children. Autistic children tend to crave or avoid certain foods based on:

  • Texture
  • Smell
  • Taste
  • Temperature

Some of this could be due to some differences in brain development, which appear as differences in how food is experienced. For example, some research suggests that people with autism have less sensitivity to sour and bitter flavors. They tend to be less attuned to smell, which can influence a lot of how food tastes.

Children with autism also have less facial feedback. This is true in their response to facial expressions, as they respond less to smiling, laughing, or frowning. This may also extend toward how they consume food. For example, a study suggested that a child’s texture preference relates to how able the child is to move their mouth, like whether they chew, suck, or crunch.

Food texture in particular is impacted by the type and amount of protein, specifically amino acid structure. This can lead to certain texture preferences and aversions.

Protein structure also impacts how the digestive system manages the food in the small intestine. Some digest easily, while others are more resistant. In a child with a fragile gut, this could cause some discomfort that then manifests as food-avoidant behaviors.

Specialized Diets

The negative effect on gut health may have an effect on brain development. Because of this, some parents have found that specific diets might work better for their children.

Gluten-free/casein-free diets and ketogenic diets are the two most common diets that parents implement for their autistic children.

Gluten-Free & Casein-Free Diets

Some parents have reported that removing dairy and wheat products from their child’s diet improved behavior and autism-related medical issues. Specifically, the proteins casein (a milk protein) and gluten (a wheat protein) may have some unintentionally harmful impacts on the child’s digestion. Intestinal issues can then negatively impact the child’s behavior.

Medical researchers are concerned that removing these two proteins from the diet can negatively impact mental and physical development.

For example, a follow-up study involving mice found that a high-fat diet actually induced more cognitive rigidity, a symptom of autism. It also appeared to dampen social memory and increased the risk of weight issues, such as being overweight or obese.

There were additional metabolic impairments, which might last a lifetime. While this is a study on mice and not humans, it does indicate the potential risks of lowering the intake of some types of foods while increasing others, so parents should be cautious when choosing a specific diet for their children.

Studies on Autism & Gluten-Free/Casein-Free Diets

A 2017 study involving 214 participants with similar diagnoses on the autism spectrum found that the GFCF diet improved communication scores based on the Autism Diagnostic Observation Schedule (ADOS) and social interaction based on the Gilliam Autism Rating Scale (GARS).

Other scores reiterated improvements after treatment with a GFCF diet compared to the control group, with remaining improvements self-reported by parents. There were no adverse events associated with the GFCF diet.

Research on Autism & Ketogenic Diets

This approach to nutrition and meal planning has been found to be an effective supportive treatment for children with epilepsy, so it is gaining traction and interest for other brain conditions like autism.

A study involving autistic models in mice showed that there were some gut benefits with the ketogenic model, which involved feeding the mice 75% ketogenic food over 10 to 14 days, with the control group receiving 13% fat in their diet. The main findings were that gut bacteria were altered, which could be useful in understanding gut and brain interactions. There was some antimicrobial effect with the ketogenic diet, which might be beneficial for certain digestive interactions.

Comparing Differing Dietary Approaches

One study gathered 45 children between the ages of 3 and 8 who were all diagnosed with autism. The children were divided into three groups. The first group went on the ketogenic diet, which is a modified form of the Atkins Diet. The second group went on the GFCF diet. The third group worked on balanced nutrition in general and otherwise had no specific diet, so they served as the control group.

At the six-month mark, both the ketogenic and gluten-free/casein-free groups had significant improvements based on two rating systems: the Childhood Autism Rating Scale and the Autism Treatment Evaluation Test. The ketogenic diet appeared to offer stronger improvement in cognition and sociability compared to the GFCF group.

It is important to note that these diets are popular as of 2020. They may reflect cultural fads more than they actually benefit children with autism.

It’s best to work with a nutritional therapist to develop a balanced eating plan instead of focusing on a trend that might not be the best for your child’s development.

The Science Behind Autism & Food Behaviors

Research has also shown that people on the autism spectrum have a higher incidence of gastrointestinal (GI) comorbidities, including indigestion, constipation, and diarrhea. In some contexts, this is referred to as a fragile gut.

A newer study reported that children who were diagnosed with autism and reportedly had a fragile gut appeared to have lower digestive enzyme activity, which may make digesting some proteins more complicated. There was also evidence that dietary peptides might enter the bloodstream by accident due to some gut barrier issues, leading to an immune response that might be associated with inflammation and discomfort.

This study suggests that some dietary changes might ease discomfort in children with this comorbidity. As children feel more comfortable, it can lead to fewer food struggles, tantrums, mood swings, or other issues that make mealtimes harder to manage.

Keeping Your Child Healthy Means Personalized Care

Rather than relying on certain fad diets, like ketogenic or gluten-free approaches, parents who are concerned about their autistic child’s dietary habits and health should work with their child’s care team. This means consulting your child’s pediatrician, ABA therapist, and a nutritional therapist.

A personalized plan that ensures your child gets enough nutrients, while supporting gut health and helping to avoid digestive discomfort, can be vital to your child’s overall mental and physical development. It’s less about specific foods that your child should eat or avoid, and more about a balanced approach to eating and nutrition.

Nutritional changes should only be a component of your overall approach to autism care. Behavior therapy will make up the bulk of the treatment plan, and ABA therapy will often include approaches to improve behaviors related to a child’s feeding if that is an issue.

Some symptoms of autism, like tantrums and ritual behaviors, can be minimized with a combination of behavior therapy to encourage the child to communicate more clearly and nutritional support to keep them healthy.