Autism – Symptoms REVERSED in New Study


Symptoms of autism were reversed in a study published in April of 2017 by Annals of Clinical and Translational Neurology.1  Five children, average age of 9 years old, received one dose of suramin – a manmade drug first synthesized in 1916.  The results were remarkable:

  • Improved scores for language
  • Improved scores for social interactions
  • Decreased restricted or repetitive behaviors

None of the improvements occurred in the placebo group.  This was the first study in the published, scientific literature to analyze the effect of suramin in a pediatric population of autistic children. And, it worked!  According to the study, after a single dose of suramin, “the rate of language, social, behavioral, and developmental improvements continued to increase for 3 weeks,” but then the symptoms began to re-appear.1

Even though the reversal of symptoms was temporary, the study demonstrates that autism may not be a genetic life-sentence; it may not be permanent.

Autism may be reversible.

It’s theorized that suramin worked by dampening the cell danger response (CDR). When cells perceive a threat that could injure or kill them, the CDR is activated. As a result, inflammation in the body increases as part of a protective mechanism. That protective response is supposed to be temporary; once the threat is removed, the CDR is supposed to be deactivated. However, in children with autism, it’s theorized that the CDR persists even after the threat has been eliminated.1,2

This new study demonstrates that the CDR in autistic children can be turned down and that “normal” metabolism can be restored.1 In other words, symptoms of autism can be reversed, at least to some degree, by lowering inflammation.

The key to reversing autism may be reducing inflammation.

We know that autism is an inflammatory disease.3,4  “It’s the inflammation that compromises brain function in children and even in adults,” according to Dr. Perlmutter, neurologist and author of The Grain Brain.5  In fact, we’re now learning that symptoms of autism, including lack of focus and characteristic behavioral traits, are “manifestations of an underlying inflammatory problem.”5  This new study supports that hypothesis – suramin decreased symptoms of autism, in part, by decreasing inflammation.1

That’s great news because it means that if you lower inflammation, you can reverse the symptoms or – at a minimum – improve quality of life.  How do you lower the inflammation?

One approach is to use a drug, like suramin.  However, it may work by addressing the symptoms.  A different approach is to address the root of the problem:

Remove the triggers that are causing the inflammation.

We know that the CDR can be triggered by the following threats:2

  • Chemical Threats: Bisphenol A, flame retardants like the brominated diphenyl ethers (BDEs), pesticides like DDT, and heavy and trace metals such as lead, mercury, cadmium, arsenic, and nickel.
  • Physical Threats: Heat, pH shock, and UV radiation.
  • Microbial Threats: Viruses, bacteria, fungi, and parasites.
  • Psychological Threats: Trauma during childhood is a known activator of the CDR and can increase the risk of many illnesses.

All of those triggers have something in common – inflammation. They all initiate an inflammatory response in the body.2  Consequently, identifying and removing those triggers is a great start to reversing inflammation. However, there is another source of inflammation; another hypothesis that is quickly gaining traction:

Autism may begin in the gut

and end in the brain.

The gut – not the brain – is most likely the origin of the pathologies commonly seen in autistic children, including lack of focus and anti-social behavior, according to Dr. Perlmutter.5  That means, autism does not begin the brain. It may actually start in the gut, as inflammation. That inflammation can cross the blood-brain barrier and affect the brain, which results in the characteristic neurological symptoms seen in individuals with autism.

That hypothesis may sound far-fetched. But, a robust set of data supports the gut-brain connection in autism, as well as other inflammatory conditions such as: obesity, Crohn’s disease, IBS, and Alzheimer’s. Here are a few examples from the scientific literature that support the gut-brain hypothesis:

  1. Gastrointestinal symptoms occur in up to 70% of children who have been diagnosed with autism spectrum disorder (ASD), which suggests the gut likely plays an important role.6
  2. Leaky gut, or increased gut permeability, is documented among children with autism. When a child has leaky gut, pathogens and toxins can enter the body, cross the blood-brain barrier and influence brain function. For example:
    • Lipopolysaccharide (LPS) is found on the cell wall of certain bacteria in the gut. Children with autism reportedly have increased levels of LPS in their blood. That’s a problem because LPS is not supposed to be in our bodies. If it enters the body, LPS can influence brain function and is associated with impaired social behavior scores.7,8
  3. Different types of bacteria have been found in the guts of autistic children compared with non-autistic children. Specifically, autistic children reportedly have less bacterial diversity, lower levels of beneficial bacteria, and higher levels of potentially harmful bacteria.9 Those differences in gut bacteria are both directly and indirectly involved with autism symptoms. For example:
    • An overgrowth of Clostridium is commonly seen in the guts of autistic children. Clostridia make propionic acid, which is a short chain fatty acid. Propionic acid can cross the blood-brain barrier and induce autism-like behaviors. In fact, when rats were injected with propionic acid, they developed repetitive motions, cognitive deficits, and impaired social interactions. In a separate study, when Clostridium was reduced, improvements were seen in autistic children.10-14
    • Autistic individuals are two times more likely to have an overgrowth of Candida – a type of yeast that release ammonia and other toxins that can induce autistic behavior.15
    • Administering daily probiotics to children with ASD “normalized” the ratio of bacteria in their gut to match the bacteria found in the guts of “healthy” children. Consequently, GI symptoms and ASD symptoms, including the ability to follow directions, improved.16-18
  4. Antibiotic exposure is considered a risk factor for developing both autism and Alzheimer’s disease because antibiotics can permanently change the composition of bacteria in your gut.19
  5. The use of acid blocking drugs can increase your risk of developing dementia by 40%, according to a study published in JAMA Neurology in 2016. The drug changes the pH of the gastrointestinal system. Consequently, the balance of “good” and “bad” bacteria can change. For example, some “bad” bacteria flourish in low pH.20
  6. Children born via cesarean section have a 2-fold greater risk of developing autism compared with children born vaginally.21  The first bacterial exposure of the baby sets their immunity and can determine the “life-long balance of immune function and inflammation,” according to Dr. Perlmutter.5  When born vaginally, babies acquire the bacteria that live inside the birth canal. That bacteria builds the gut and skin microflora of the baby. In contrast, with a c-section, the baby is initially exposed to the bacteria on the doctor’s gloves and the surrounding environment.

Clearly, a connection exists between the gut, inflammation, and disease – including autism. But, if the gut is the root of the inflammation, how do we stop the gut from being inflamed?

Again, it comes down to identifying the triggers. What’s triggering the gut to be inflamed? According to Dr. Perlmutter, the key is bacteria.

“We lower inflammation by taking care of our gut bacteria.

We do that primarily through the diet.”

Each child is unique. Consequently, each child has their own dietary and environmental triggers that must be identified in order to reverse the inflammation. However, Dr. Perlmutter provides general recommendations based on triggers that are common in inflammatory conditions, including autism:

  1. Avoid GMOs/Glyphosate – Glyphosate is an herbicide that is sprayed on lawns, gardens, and much of our food supply. It can change your gut bacteria in a detrimental way. Consequently, buy organic food when possible.
  2. Less Sugar –Sugar tends to be inflammatory, so eliminate refined sugars when possible.
  3. No Artificial Sweeteners – These can have a detrimental effect on the gut bacteria, resulting in inflammation.
  4. Less Processed Foods – Processed foods tend to be lower in fiber.  They can also contain synthetic chemicals that may contribute to inflammation.
  5. More Fiber – In 2014, the Journal of Nutrition reported that children who consumed more fiber were able to maintain better focus than children who consumed less fiber. Why? Fiber feeds the “good” bacteria in the gut, which can lower inflammation throughout the body. It’s also important to include prebiotic fiber in the diet because it nurtures gut bacteria. Examples of prebiotic fiber include: asparagus, garlic, onion, chicory root, leeks, dandelion greens, and Mexican yam. If your child will not consume those foods, Dr. Perlmutter recommends acacia gum as a supplement.
  6. More Fat – Fat can be good for both the brain and the gut. In fact, higher fat diets are emerging as a key component in reducing inflammation. In animal ASD models, a ketogenic diet (high fat/low carbohydrate) increased sociability, improved social communication, and decreased repetitive behaviors.22, 23  Dr. Perlmutter recommends grass-fed beef, wild-caught fish, nuts, seeds, and coconut oil.
  7. Gluten Free – Foods containing gluten can be inflammatory. For example, wheat contains a gluten protein called gliadin. Gliadin effects the gut lining “in all humans,” according to Dr. Perlmutter.  And, remember: corn and rice contain a form of gluten too.  Studies have shown a decrease in ASD behavior, physiological symptoms, and social behaviors when following a gluten-free and/or casein-free diet.24-26
  8. Probiotics – Dr. Perlmutter recommends a potent (containing billions of bacteria per dose) probiotic containing 12-14 different types of bacteria with a shelf life of 1-2 years.  Specifically, Lactobacillus plantarum and Lactobacillus rhamnosus can assist in healing the lining of the gut.
  9. Adequate levels of vitamin D – Vitamin D deficiency can lead to inflammation. Dr. Perlmutter recommends keeping the vitamin D level in the blood around 80-90 nmol/L.

Dr. Perlmutter’s list is a great starting point for reducing inflammation in children who already have autism. But, like many other conditions, our current medical system takes a reactionary approach to autism – wait until symptoms appear and then treat the condition.

What if you could prevent autism from developing in the first place?

That’s exactly what Dr. Perlmutter would like to see – a preventative approach to autism. He believes we should all think about prevention, particularly during the prenatal and postnatal periods.

During the prenatal period, he recommends consuming adequate levels of DHA, folic acid, iron, and a probiotic. In addition, during pregnancy, the following factors have been associated with ASD and may be risk factors:5

  • Antibiotics
  • Mother’s diet – particularly heavy metal and glyphosate exposure
  • Gestational diabetes
  • Obesity

During the postnatal period, breastfeeding is associated with a decreased risk for ASD, partly because bacteria on the mother’s skin helps the baby’s immune system develop.27, 28  Breast milk also contains oligosaccharides, which nurture the developing microbiome. In addition, if your child has GI issues at birth – such as constipation or diarrhea – that is likely “an indication that something bigger may be at play.”5  Dr. Perlmutter recommends a proactive, preventative approach – get to the root of the problem before it possibly turns into a larger issue.

The fact that the conversation is moving towards reversal of symptoms and prevention of autism means there is a new sense of hope:

There’s hope that autism is not a genetic life-sentence.

There’s hope that diet can help reverse autism.

There’s hope that, some day, we will speak of autism as a preventable condition.



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Dr. Sina McCullough
Dr. Sina McCullough is the author of "Beyond Labels: A Doctor and a Farmer Conquer Food Confusion One Bite at a Time" and "Hands Off My Food!: How Government and Industry Have Corrupted Our Food and Easy Ways to Fight Back." You can connect with her at Sina holds a Ph.D. in Nutritional Science and a B.S. in Neurobiology, Physiology, and Behavior, both from the University of California at Davis. She taught Biochemistry and Bioenergetics at UC Davis before becoming the Director of Research and Development for a supplement company. Dr. McCullough homeschools her two children and offers a limited number of consultations for both individuals and companies.