Autism and Nutrient Therapy: 5 Possible Nutrient Deficiencies in ASD

by | Apr 4, 2022 | Autism, Blog, Featured, Gut Health, Nutrition | 0 comments

There are a number of genetic and environmental factors that may play a role in the development and treatment of autism. A significant and growing body of research evidence suggests that nutrient deficiencies may be an important factor in ASD (Autism Spectrum Disorder). In my practice, I’ve found that uncovering nutrient deficiencies and using nutrient therapy in autism can make a significant difference in the health, well-being, and daily life of many children with autism when management of symptoms is required.

Today I want to discuss the role of nutrient therapy in autism. You will learn about 5 of the possible nutrient deficiencies in autism that I consider important.

What Is Autism?

Autism spectrum disorder (ASD) or autism refers to a range of conditions that can cause significant social, behavioral, and communication challenges. According to the Government of Canada, about 1 in 66 children are diagnosed with autism in Canada (1). According to the Centers for Disease Control and Prevention (CDC), autism affects about 1 in 44 children in the US (2). These official numbers may be higher in reality since diagnosis can come with financial and emotional challenges and is not available for everyone. Adult diagnosis of autism is increasingly prevalent as well. About 2% of adults are diagnosed with autism (3, 4).

Autism has various subtypes that may be influenced by both genetic and environmental factors. The symptoms of autism may range from person to person. For example, learning, thinking, and problem-solving abilities may range anywhere from highly gifted to severely challenged. Social interactions may be incredibly challenging for some but less so for others. While many people with autism can lead a healthy and productive life, others may need help with their daily lives for their entire life.

Research to understand autism and treatment options is still ongoing. There are many factors that may influence the development and symptoms of autism, including genetics, family history, other medical issues, other mental health challenges, and environmental factors. Treatment of autism often involves a group of healthcare providers from various areas of expertise.

Gastrointestinal issues and nutrient deficiencies are some common yet often overlooked factors that can influence autism. These can be considered “comorbidities”. In my practice, I’ve found that checking nutritional status and uncovering nutrient deficiencies in autism and using nutrient therapy for children with autism can be very helpful for improving health, development, and well-being  when additional assistance is needed (5).

Autism and Nutrient Therapy: Top 5 Possible Nutrient Deficiencies

Nutritional deficiencies are quite common in autism spectrum disorders. Many children with autism struggle with picky eating and food selectivity, making it difficult for parents or caregivers to ensure their nutritional needs are being met. Gut health issues, gastrointestinal distress, and immune system issues may also lead to nutrient deficiencies in autistic children or adults. Following an unhealthy diet instead of a sugar-free, casein-free, and gluten-free diet rich in nutrient-dense whole foods makes nutrient deficiencies even more common, especially without taking mineral supplements, multivitamins, or other supplements. 

This makes dietary interventions and using nutritional approaches even more important. Let’s look at 5 possible nutrient deficiencies in autism and how to use nutrient therapy in ASD.

Vitamin B12

Vitamin B12 is a type of B vitamin that plays an important role in red blood cell formation, nerve function, cell metabolism, and DNA production. It is critical for your brain and mental health (7, 8, 9, 10). Unfortunately, deficiencies in vitamin B12 are common. Meeting your vitamin B12 needs without supplementation is very difficult, especially if you are on a vegetarian or vegan diet.

Vitamin B12 deficiencies are common in autism. Having an MTHFR gene mutation may also increase the risk of B12 deficiencies (11, 12). A 2016 randomized placebo-controlled trial published in the Journal of Child and Adolescent Psychopharmacology has found that using vitamin B12 injections in children has led to significant improvements in symptoms of autism (13). 

Beyond vitamin B12, other B vitamins, including thiamine (b1), biotin (B7), and folate (B9) may also support those with autism (11). A 2018 randomized controlled trial published in Nutrients has found that supplementing with vitamin B6, B6, B9, and B12 has improved symptoms of autism (14). Supplementing with vitamin B12 and a vitamin B complex may be an important part of nutrient therapy for autism.


Glutathione is produced by your liver and is made from the amino acids glycine, cysteine, and glutamic acid. It plays a critical role in tissue building, tissue repair, and immune health. Glutathione is a powerful antioxidant that may help to support detoxification and to reduce oxidative stress. It also helps to manage the brain chemical, glutamate.

Glutathione has been shown to help those with autism. A 2020 review published in Free Radical Biology and Medicine has found that glutathione plays a critical role in autism by supporting the intracellular redox balance (15). A glutathione redox imbalance is characterized by low glutathione levels, high oxidized glutathione levels, and abnormal expression of glutathione-related enzymes. It plays a factor in autism and other neurodevelopmental disorders. Glutathione supplementation and improving glutathione redox balance may help. As demonstrated by a 2010 case report I published in JOM, I found in my personal practice that glutathione supplementation can significantly support the health of my patients with autism (16).

Omega-3 Fatty Acids

Omega-3 fatty acids are anti-inflammatory essential fatty acids found in food, such as fish and certain seeds, and in dietary supplements, such as fish oil and algae oil. There are three main types of omega-3s: eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA). DHA and EPA are the most important omega-3 fatty acids. They are mainly found in fish, seafood, fish oil supplements, and algae oil supplements. ALA is mainly found in flaxseeds, chia seeds, hemp seeds, soybeans, and plant oils, and from ALA seed supplements. Your body can convert ALA into EPA and DHA, however, only in small amounts, so getting EPA and DHA from foods and supplements is critical. 

Omega-3 fatty acids may help to reduce inflammation, support your brain function, improve your mood, and reduce the risk of heart disease, metabolic syndrome, and chronic illness (17, 18, 19, 20, 21, 22, 23). Omega-3 fatty acids may also play a role in nutrient therapies in autism. A 2014 paper published in Medical Hypothesis has found that omega-3 fatty acids may help autism, attention-deficit hyperactivity disorder (ADHD), and cerebral palsy (17). A 2018 randomized trial has found that supplementing with omega-3 DHA and EPA has improved symptoms of autism (13). 

Omega-3 fatty acids may help to reduce inflammation, including neuroinflammation. Neuroinflammation can impair cognitive function and cause brain or mental health challenges. Improving neuroinflammation thus may help to improve inflammation-related symptoms of autism and other related conditions. Omega-3 fatty acids are involved in the synthesis of important brain chemicals, such as serotonin and dopamine, thus helping to improve mood and overall mental well-being. To improve your omega-3 levels as part of nutrient therapy for autism, I recommend eating wild-caught fresh fish, such as salmon, mackerel, and rainbow trout (cautiously due to mercury content), eating flax seeds, chia seeds, hemp seeds, and walnuts, and taking a high-quality omega-3 fish oil supplement with EPA and DHA.


Carnitine is an amino acid. Carnitine can be found in beef, poultry, fish, beans, avocados, asparagus. Carnitine is a broad term used for different types of compounds under the same umbrella. L-carnitine is a common form of carnitine found in your body and supplement. Other forms of carnitine supplements include acetyl-L-carnitine and propionyl-L-carnitine.

Carnitine has an important role in energy production. It helps to transport long-chain fatty acids to your mitochondria. There they are burned to produce energy. It also helps to prevent the accumulation of toxic compounds generated by cellular organelles. Carnitine is also critical for your brain function, heart health, skeletal and cardiac muscles, and other bodily functions (24, 25, 26).

Carnitine may also be beneficial for those with autism. Children, adolescents, and adults with autism often have lower levels of carnitine that may affect their body’s ability to properly use fatty acids necessary for cognitive and social development. A 2018 randomized trial has found that supplementing with carnitine has improved symptoms of autism (13). A 2019 review published in Molecules has also found that carnitine may be a great part of a nutrient therapy for autism (27). You may benefit from eating carnitine-rich foods and taking a carnitine supplement. 

Vitamin D

Vitamin D is an important vitamin that your body can synthesize as the sun hits your skin. Unlike other vitamins, vitamin D actually functions like a hormone, not a vitamin. This means that vitamin D helps to regulate hundreds of genes and supports countless mechanisms in your body. Vitamin D is critical for brain, mental, nervous system, immune, bone, and cardiovascular health.

Since vitamin D is necessary for brain development, it’s not surprising that vitamin D deficiency may play a role in autism. Low levels of vitamin D have been linked to lower language scores and more behavioral challenges in autism. A 2014 case-control study published in the Journal of Pediatric Neurosciences has found that vitamin D deficiency may increase the risk of autism symptoms in children and vitamin D supplementation may reduce risks and improve symptoms (28). A 2017 study published in Nutritional Neuroscience has found that supplementation with vitamin D may improve autism in children (29). 

A 2016 study published in BJPsych Open has found that vitamin D deficiency during pregnancy may also increase the risk of autism (30), as did a 2019 study published in Nature which found that maternal and neonatal vitamin D deficiency may both increase the risk of ASD (31). Supplementing with vitamin D may be beneficial for both those with autism and expecting mothers.

Other Tips for Nutrient Therapy for Autism

Zinc, magnesium, vitamin A, and co-enzyme Q-10 supplementation may be beneficial (14, 16, 32, 33) as additional nutrients to consider. Beyond uncovering and addressing these nutrient deficiencies in autism, other dietary strategies may be helpful as well. I’ve found that following a sugar-free, gluten-free (GF), and casein-free (CF) whole foods diet can make significant differences for children with autism spectrum disorders and other developmental disorders (16). Research has found that a subset of large children with ASD have gut permeability issues, or “leaky gut” (34, 35), which can result in poor nutrient absorption and deficiencies. Gluten and casein, wheat and dairy protein respectively, would be potential triggers for the gut lining becoming leaky.  Checking for food intolerances, food sensitivities, and removing any triggering foods may be helpful. Often I will recommend a GFCF food elimination diet for 3 months to best assess the role that dietary restriction might play in a carefully managed treatment plan.

Next Steps

If you are looking for personalized tips and dietary recommendations for autism (for yourself or your child!), or want to improve your health, wellness, and mental well-being, I welcome you to start a personalized functional medicine consultation with me. You may book your consultation here. 

Learn more about working with Dr. Gannage