10 Nutrients Most Deficient in Autism


Published in the Autism Eye Magazine, March 2023

Research shows that many children with autism have nutrient deficiencies, which can contribute to autism symptoms. These deficiencies can be due to various reasons, including digestive problems, picky eating habits, food sensitivities, gut dysbiosis, metabolic disorders, and nutrient-depleting medications. The followings are some of the essential nutrients that children with autism are often missing and the top ten supplements that can help support their development and well-being. You will also find a list of the food sources of each nutrient in Table 1 below.


1. Omega-3 Fatty Acids: Omega-3 fatty acids are crucial in brain development and function. Studies have shown that children with autism have low levels of omega-3 fatty acids in their blood. Supplementation with fish oil, especially supplements containing higher levels of DHA, helps increase the levels of these essential fatty acids in the body. Flaxseed oil or algae-based oils are alternatives source but is less bioavailable.


2. Vitamin D: Vitamin D is essential for proper bone growth and development and for the appropriate functioning of the immune system. Low vitamin D levels, can lead to various health problems, including an increased risk of infections and decreased bone density. Getting vitamin D from sunshine is ideal, but other sources, such as cod liver oil and foods such as salmon and organic eggs, can also be helpful. Always supplement using vitamin D3 along with K2. Most high-quality supplements combine the two in the correct ratio.


3. Magnesium: Magnesium is an essential mineral involved in numerous physiological processes in the body, including energy production, muscle function, and the proper functioning of the nervous system. In my experience, this is one of the most common and significant deficiencies seen in children with autism, which can contribute to symptoms such as anxiety, depression, constipation, poor focus and concentration, stimming, and sleep disturbances. Magnesium supplements vary enormously. Certain forms like magnesium citrate and oxide are best used if addressing constipation. Magnesium chloride and sulfate (found in Epsom salts) are great for relaxation. The only types of magnesium that can cross the blood-brain barrier and have direct anti-inflammatory and neurological benefits are magnesium glycinate and threonate.


4. Zinc: Zinc is an essential mineral involved in many physiological processes, including the proper functioning of the immune system and the metabolism of proteins and DNA. Low zinc levels can contribute to various health problems, including poor appetite and growth, impaired immune function, and decreased cognitive function. Research studies have shown that zinc picolinate is the most effective and bioavailable form of zinc supplement.


5. Vitamin B6: Vitamin B6, also known as pyridoxine, is involved in the production of neurotransmitters, the proper functioning of the immune system, and the metabolism of proteins. Children with autism often have low levels of vitamin B6, which can contribute to symptoms such as sleep disturbances, anxiety, and depression. Vitamin B6 supplements can be taken as pyridoxine HCl or pyridoxal-5-phosphate.


6. Folate: Folate is a B vitamin essential for the proper functioning of the nervous system and the metabolism of DNA. Low folate levels can contribute to symptoms such as fatigue, depression, and anaemia. The types of folate supplements that work best are Methyl-folate or folinic acid. The right form of folate supplementation will very much depend on the needs and epigenetics of the child. Research has shown that dairy can block folate receptors.Dairy removal is the number one recommendation if we suspect folate receptor antibody issues or find antibodies through testing.


7. Iron: Iron is essential in producing haemoglobin, which carries oxygen to the body’s tissues. Low levels of bioavailable iron can lead to symptoms such as fatigue, decreased immune function, and poor cognitive function. In rare cases, iron supplements are appropriate. Most of the time, it’s not the lack of iron that is the problem but the lack of bio-available iron due to copper deficiency. It is imperative that you work with a knowledgeable practitioner before supplementing with iron.


8. Vitamin C: Vitamin C is a powerful antioxidant that helps to support the immune system and reduce inflammation in the body. Low vitamin C levels can contribute to symptoms such as fatigue, decreased immune function, and increased susceptibility to infections. Vitamin C supplements can be taken in the form of ascorbic acid or sodium ascorbate; however, we generally recommend wholefood vitamin C found in acerola cherries or Camu Camu.


9. Vitamin B12: Vitamin B12 is essential in producing red blood cells and properly functioning the nervous system. Low vitamin B12 levels can contribute to symptoms such as fatigue, anaemia, and cognitive problems. Vitamin B12 supplementation is very tricky. Active forms of B12, such as methylcobalamin, can be tolerated well by some and very poorly by others. Also, for B12 to have the desired impact, it is essential to have adequate levels of specific minerals like selenium, lithium, molybdenum, and riboflavin.


10. Probiotics: The most comprehensive meta-analysis to date reveals that children with ASD are more than four-fold more likely to develop GI problems. Probiotics can be helpful when supplemented at the right stage of the gut health programme. Rotating probiotic strains and complementing them with prebiotics are key to achieving long-term gains. In terms of individual probiotic strains, the following have been in the spotlight with regard to helping specific autistic symptoms.

  1. a) Lactobacillus rhamnosus, which has been shown to reduce anxiety and stress-related behaviours in children with autism. It has also been found to improve social and communicative behaviours in autistic children.
  1. b) Bifidobacterium longum has been studied for its potential to reduce gastrointestinal symptoms in children with autism. It has been found to reduce inflammation in the gut and improve social behaviours in autistic children.
  1. c) Bifidobacterium breve has been found to reduce gut inflammation, gastrointestinal symptoms, and anxiety in autistic children.

Autistic children often have nutrient deficiencies affecting their physical and mental health and well-being. By supplementing with the nutrients mentioned above, as well as ensuring a diet rich in these nutrients, parents and caregivers can help to support their child’s development and well-being. It is important to note that supplementation should always be taken under the guidance of a healthcare professional and in conjunction with a balanced diet.

This article is not intended as medical advice and is for educational purposes only.

Table 1 of foods containing the nutrients mentioned

Omega 3 fatty acids: Salmon,  Mackerel, Herring,  Chia Seeds, Walnuts, Flaxseeds,  Sardines, Oysters, Tuna, Anchovies

Vitamin D: Salmon, Mackerel, Tuna,  Egg Yolk, Mushrooms, Beef Liver, Cheese, Sardines, Milk, Fortified Cereals

Magnesium: It is recommended that you get bio-available magnesium from Salmon, Mackerel, Tuna, Sardines, Egg yolks, Beef liver, Avocado, Dark chocolate, Black beans.

Zinc: Oysters, Beef, Lamb, Crab, Pork, Cashews, Chickpeas, Baked Beans, Dark Chocolate, Mushrooms

Vitamin B6: Turkey Breast, Pistachios, Sunflower Seeds, Spinach, Avocado, Bananas, Beef, Sardines, Sweet Potato, Tuna

Folate: Beef liver, Avocado, Pinto beans, Lentils, Asparagus, Brussels sprouts, sunflower seeds.

Iron: liver, beef, oysters, lentils, kidney beans, pumpkin seeds, dark chocolate.

Vitamin C: Kiwi, Papaya, Strawberries, Oranges, Pineapple, Cantaloupe, Mango, Grapefruit, Blueberries, Watermelon

B12: Beef, Liver, Trout, Salmon, Tuna, Yogurt, Milk, Egg Yolk, Clams

Probiotics Yoghurt, Milk and Water Kefir, Tempeh, Sauerkraut , Kimchi, Miso Soup, Kombucha, Pickles



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