Autism Research Shows Benefit of Omega-3 Fatty Acids

Dr. Sears Blog: Omega-3s Could Minimize the Risk of AutismAutism can be one of the most challenging conditions that occurs in a family. Autism is a mental condition that begins in early childhood and is characterized by difficulty in communicating and forming relationships with other people. But what if autism is an omega-3 deficiency condition?

While improved diagnosis and awareness of autism may partly explain its increase through the years, this is not the main reason for its almost exponential growth rate since 1975. The popular suspect that autism is caused by vaccines has never been substantiated, and the removal of mercury from vaccines in 1995 has not impeded its growth in the U.S. According to the Centers for Disease Control (CDC). The current rate of autism in the U.S. is about 1 in 68 or about 1.5% of children.

Signs of autism can be observed as early as 12 to 18 months, and are often quite clear by 24 months. That may provide a clue to its underlying cause. The first 1,000 days of life for a child are critical for brain development, and this includes the nine months of those spent in the womb. This means by two years after birth, either the child’s neural wiring is established correctly or the child may have severe structural problems for the rest of his or her life.

Potential Links to the Development of Autism

A recent review published in 2016 may provide some insight into the growing epidemic of autism.1 A strong argument can be made that autism may be caused by inflammation of the nervous tissue in the child’s brain (aka, neuroinflammation). This is caused by a combination of factors, including maternal inflammation during fetal development, lack of omega-3 fatty acids, and gut-induced inflammation in the infant during the first two years of life. All of these dietary factors can lead to neuroinflammation in the child’s brain, disrupting the critical development of neural networks.2

Maternal Inflammation During Fetal Development

Maternal infection has been linked to autism. During the rubella pandemic in 1964, there was a nearly 200-fold increase in autism in the children born to infected mothers.3,4 A possible explanation is the increase in the levels of inflammatory cytokines caused by the viral infection crossing the placental barrier and causing increased neuroinflammation in the developing fetal brain.5,6 However, you don’t need maternal infection to induce cytokine production in the fetal brain.

Lack of Omega-3 Fatty Acids and a Leaky Gut

A leaky gut can increase the entry of microbial fragments such as lipopolysaccharide (LPS), which induce the same cytokine cascade that can disrupt neural development in the fetus.7 In addition, a deficiency of omega-3 fatty acids in the maternal diet can lead to a depletion of neurotransmitters (like serotonin and dopamine) that are known to be lower in the frontal cortex of autistic children.8,9 This correlates well with lower levels of omega-3 fatty acids in the blood of children with autism.10,11

Gut-Induced Inflammation

The composition of the microbes in the gut can also be linked to autism. Besides being a source of microbial fragments that can induce inflammation if they enter the blood, some of the fermentation products such as the short chain fatty acid (propionic acid) coming from certain strains of microbes have been shown in studies to trigger autism-like behavior when directly injected into the brain.12,13

The Autism Epidemic—Hope for the Future

All of this information might indicate there is little hope for the future of reversing the epidemic of autism. But there is a way out. It’s an anti-inflammatory diet, and specifically the Zone Diet supplemented with high dose EPA and DHA.

Obviously, the best defense against autism is not having it develop in the first place. This means keeping inflammation under control during pregnancy and during the first two years after birth. The Zone Diet is rich in non-starchy vegetables that contain fermentable fiber. This will stabilize the gut barrier, decreasing the likelihood of bacterial fragments, which can cause neuroinflammation in both the fetal and postnatal brain. At the same time, adequate levels of EPA and DHA will reduce the overproduction of inflammatory cytokines caused by infection.

My Recommended Intake of Omega-3 Fatty Acids For Pregnant Women

My recommended level of EPA and DHA supplementation during pregnancy has always been 2.5 grams of EPA and DHA per day.

A recent study has demonstrated that when pregnant women took this level of EPA and DHA, there was a 31% reduction of the incidence of asthma in their children over the next six years.14 This is even more relevant since another recent study has indicated that pregnant American mothers and American women of child-bearing ages appear to be highly deficient in omega-3 fatty acids.15 How deficient compared to my recommendations of 2.5 grams of EPA and DHA per day? The intake of EPA and DHA was between 78 mg (in non-Hispanic white women) to 142 mg per day (for Asian-American women). These intakes are 95% lower than my recommendations. In addition, you need adequate levels of omega-3 fatty acids to reduce a leaky gut16 as well as reducing the levels of the gut microbes that produce propionic acid.17

The Right Amount of EPA and DHA for Children After Birth

After birth, the brain is the most rapidly growing organ in the child. It needs a lot of EPA and DHA for that growth. In Norway, it is the national mandate that a child should get 800 mg of EPA and DHA for the first year after birth. In one study that looked at children whose mothers actually followed that suggestion, their likelihood of developing type 1 diabetes (another auto-immune disorder like asthma) was reduced by 31%.18 So what do I recommend for a child after birth? For the first year, I recommend 1,000 mg of EPA and DHA per day, increasing to 1,500 mg. of EPA and DHA per day by age 1, and to 2,500 mg (2.5 grams) of EPA and DHA after the age of 2 and thereafter. This is exactly the schedule my grandson is on.

What About Children with Autism and Other Omega-3 Deficient Conditions Today?

There is research that with the proper dose, omega-3 fatty acids can benefit children with autism, autism spectrum disorders or other neurological disorders such as ADHD and childhood depression.

In one study, supplementation with EPA and DHA reduced hyperactivity in children with autism.19 Likewise, other studies have reported benefits.20-22

Proper dosage is key. Without a therapeutic dose, you will observe results consistent with a placebo. This is especially true for omega-3 fatty acids and neurological conditions. As I have demonstrated in my previous studies using high-omega-3 fatty acids in treating ADHD,23 severe brain trauma,24 and childhood depression,25 you need a therapeutic dose of EPA and DHA with these conditions, and it is usually quite high (greater than 10–15 grams of EPA and DHA per day). This means the fish oil has to be extremely pure, and you need an objective blood marker to indicate the correct dose to be maintained, probably for a lifetime.

OmegaRx 2 sets the highest purity standard for any fish oil product in the world today, and the Zone Cellular Inflammation Test Kit indicates whether you and your child need more or less to reach the necessary range of the AA/EPA ratio (between 1.5 and 3) to control existing neuroinflammation.

There is no miracle treatment for autism, but there are dietary interventions based on science that can be of benefit. I believe high-dose EPA and DHA is one of those.


  1. Madore C et al. “Neuroinflammation in autism.” Neural Plasticity 2016:3597209 (2016).
  2. Morgan JT et al. “Microglial activation and increased microglial density observed in the dorsolateral prefrontal cortex in autism.” Biol Pychiatry 68:368-376 (2010).
  3. Chess S. “Autism in children wit congenital rubella.” J Autism Childhood Schizophrenia 1:33-47 (1971).
  4. Chess S. “Follow-up report on autism in congenital rebella.” J Autism and Childhood Schizophrenia 7:69-81 (1977).
  5. Patterson PH. “Maternal infection and immune involvement in autism.” Trends in Mol Med 17:389-394 (2011).
  6. Ashdown H et al. “The role of cytokines in mediating effects of prenatal infection on the fetus.” Mol Psychiarty 11:47-55 (2006).
  7. Harvey L and Boksa P. “Prenatal and postnatal animal models of immune activation: relevance to a range of neurodevelopmental disorders.” Development Neurobiology 72:1335-1348 (2012).
  8. Innis SM and Owens S. “Dietary fatty acid composition in pregnancy alters neurite membrane fatty acids and dopamine in newborn mice.” Mol Autism 6:18 (2001).
  9. Pardo CA and Eerhart CG. “The neurobiology of autism.” Brain Pathology 17:434-447 (2003).
  10. Van Cassel S et al. “Plasma fatty acid levels in autistic children.” Prostaglandins Leukotrienes and Essential Fatty Acids 65:1-7 (2001).
  11. Jory J. “Abnormal fatty acids in Canadian children with autism.” Nutrition 32:474-477 (2006).
  12. MacFabe DF et al. “Effects of the enteric bacterial metabolic product propionic acid on object-directed behavior, social behavior, cognition, and neuroinflammation in adolescent rats: Relevance to autism spectrum disorder.” Behav Brain Res 217:47-54 (2001).
  13. Foley KA et al. “Pre- and neonatal exposure to lipopolysaccharide or the enteric metabolite, propionic acid, alters development and behavior in adolescent rates in a sexually dimorphic manner.” PLoS One 9:e87072 (2014).
  14. Bisgaard H et al. “Fish oil–derived fatty acids in pregnancy and wheeze and asthma in offspring.” N Engl J Med 375 (26): 2530-2539 (2016).
  15. Nordgren TM et al. “Omega-3 fatty acid intake of pregnant women and women of childbearing age in the United States: Potential for deficiency? Nutrients 9:197 (2017).
  16. Kaliannan K et al. “A host-microbiome interaction mediates the opposing effects of omega-6 and omega-3 fatty acids on metabolic endotoxemia.” Sci Reports 5:11276 (2015).
  17. Ghosh S et al. “Diets rich in n-6 PUFA induce intestinal microbial dysbiosis in aged mice.” Brit J Nutr 110: 515-514 (2013).
  18. Stene LC et al. “Use of cod liver oil during the first year of life is associated with lower risk of childhood-onset type 1 diabetes.” Am J Clin Nutr 78:1128-1134 (2003).
  19. Amminger GF et al. “Omega-3 fatty acids supplementation in children with autism.” Biol Psychiatry61:545-554 (2007).
  20. Bent S et al. “A pilot randomized controlled trial of omega-3 fatty acids for autism spectrum disorder.” J Autism Develop Disorders 41:545-554 (2011)
  21. Meguid NA et al. “Role of polyunsaturated fatty acids in the management of Egyptian children with autism.” Clin Bioch 41: 1044-1048 (2008).
  22. Ooi YP et al. “Omega-3 fatty acids in the management of autism spectrum disorders.” Eur J Clin Nutr 69:969-971 (2015).
  23. Sorgi PJ et al. “Effects of an open-label pilot study with high-dose EPA/DHA concentrates on plasma phospholipids and behavior in children with attention deficit hyperactivity disorder.” Nutr J 13:16 (2007).
  24. Sears B et al. “Therapeutic uses of high-dose omega-3 fatty acids to treat comatose patients with severe brain injury.” PharmaNutrition 1: 86-89 (2013).
  25. McNamara RK et al. “Dissociation of C-reactive protein levels from long-chain omega-3 fatty acid status and anti-depressant response in adolescents with major depressive disorder: an open-label dose-ranging trial.” J Nutr Therapeutics 2:235-243 (2013).

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About Dr. Barry Sears

Dr. Barry Sears is a leading authority on the impact of the diet on hormonal response, genetic expression, and inflammation. A former research scientist at the Boston University School of Medicine and the Massachusetts Institute of Technology, Dr. Sears has dedicated his research efforts over the past 45 years to the study of lipids. He has published 40 scientific articles and holds 14 U.S. patents in the areas of intravenous drug delivery systems and hormonal regulation for the treatment of cardiovascular disease. He has also written 14 books, including the New York Times #1 best-seller, The Zone, which have sold more than 6 million copies in the U.S. and have been translated into 22 different languages.


  1. Miles Potts

    My sister sent me this article – my 21 month old daughter was just diagnosed with Moderate Autism. I think like most parents that get news like this, I want to start something immediately to help her. I researched more and found that Autism Speaks ran a test on Omeg-3 and its effects and found that it proved no benefit.

    Regardless, I will try this diet. I want to do everything I can for her. But I would be interested in hearing any counter thoughts to the study that was conducted by Autism Speaks.


    Please help if you can .If not , please advise so.
    Please google”Hugs for Noah” .I believe your knowledge can help.
    If I am incorrect, please tell me.
    PLEASE help.
    As always

  3. TRM

    Leaky gut can be caused by exposure to glyphosate (Roundup). Since they started desiccating (drying) conventional cereal crops with Roundup just before harvest you have to skip all grains (easy for us zoners) and the barley and oats need to be organic.

    The gut biome is getting more attention these days. Plays a huge part in immunity, neurotransmitter production and inflammation.


    Have you analysed your grandson’s blood?
    Would you expect the AA/EPA to be 1.5- 3.0 ?
    As always#


    The reason one needs apparently high levels of (DHA and EPA) in the blood to truly benefit is a fundamental principle of Chemical Engineering.
    There must be a sufficient concentration gradient for mass transfer across the blood/cell interface .
    A placebo concentration is insufficient.
    As always#

  6. Mark McGinn

    Barry, From the studies you are researching does it seem like certain strains of bacteria cause these positive or negative inflammatory effects through their short chain fatty acid byproducts like butyrate or propionic acid, or is a larger diversity of gut microbes in general more beneficial ?

  7. mark mcginn

    This article is fascinating, especially considering the gut inflammation connection, and since Dr Sears has been right many years in advance on other biochemical based health issues, I would not be quick to dismiss this early evidence he is pointing to. No one understands inflammation the way Dr Sears does, great article Barry.

  8. Karen Isaacson

    They can do MRI scans in babies at risk for autism due to an older sibling having it and see the structural changes at 6 months (UW research in Seattle). I have autism and resent **** like this being touted as ‘scientific’ and ‘authoritative’ when all it is is ********.

    • Mary Perry

      Hi Karen,
      Thank you so much for your feedback. Dr. Sears is the first to state that autism is multi-factorial and that new literature is always emerging. This article presents his perspective that there are dietary interventions based on science that may help individuals with this condition, while recognizing that autism is complex.


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