What Causes Autism? Gut Health is Likely an Important Factor

What Causes Autism? Gut Health is Likely an Important FactorWith cases of autism spectrum disorder (ASD) becoming increasingly common, people want to know, what causes autism? The cause is likely multifaceted, involving both genetic factors and environmental ones, like exposure to toxins and diet. Accumulating evidence also shows that children with ASD have an altered composition of bacteria in the gut. This research suggests that using probiotics for autism treatment might be an especially helpful strategy for reducing symptoms.

Autism is associated with digestive problems

It is extremely common for people with ASD to experience gastrointestinal symptoms like diarrhea, constipation, reflux, abdominal pain, gas, and abnormal stools. While not all people with ASD have these symptoms, those who do often have more severe irritability, anxiety, and social withdrawal.[1]

The gut-brain axis

Clearly, there is some link between ASD and the health of the gut. But what does our digestion have to do with the brain? The gut-brain axis describes the ability of signals from the brain and gastrointestinal tract to affect each other.[2] The vagus nerve serves as a line of communication between the gut and the brain.[3] It is likely that the immune system also plays a role in this communication system.[2]

The bacteria living in our gut (called the microbiome) can influence the gut-brain axis. Research suggests that the colonies of bacteria in the gastrointestinal tract can initiate signals to neural circuits in the brain involved in things like motor control and anxiety. Although the exact mechanism is still unclear, the gut microbiome does have the ability to affect our behavior.[2]

Gut bacteria imbalances in autism

Several studies using laboratory animals have found that imbalances in the gut microbiome are associated with autism.[4] In humans, certain bacteria types are often elevated or reduced in children with ASD compared to healthy controls.[3] Autism in children has been associated with a distinct composition of bacteria and a reduced diversity of bacterial species in the microbiome.[5]

The solution? Probiotics

If an imbalanced gut microbiome is associated with ASD, then what can we do about it? Probiotics are live sources of healthy bacteria that can help to balance the bacterial composition of the gastrointestinal tract. Probiotics can help a variety of medical conditions, like inflammatory bowel syndrome, by restoring the gut microbiome to normal conditions. They are also known to affect brain functioning and behavioral conditions.[1]

In laboratory studies, supplementation with a probiotic can help restore proper gastrointestinal functioning in ASD models, as well as ameliorate symptoms like anxiety and social withdrawal.[4] While larger studies are needed to confirm this, researchers strongly believe that probiotics can be extremely effective treatment tools for ASD.[1,3]

Find a high quality probiotic supplement to try as a treatment for ASD, or try eating more probiotic and prebiotic-rich foods. One laboratory study using the strain Bacteroides fragilis produced good results.[6]

Share your experience

Do you or someone you know use probiotics for autism? Does it help? Please share any experience you have with probiotics or other natural options for autism in the comments section below.


[1] Gastroenterol Res Pract. 2011;2011:161358.

[2] Brain Behav Immun. 2014 Mar;37:197-206.

[3] PLoS One. 2013 Oct 9;8(10):e76993.

[4] Cell. 2013 Dec 19;155(7):1451-63.

[5] PLoS One. 2013 Jul 3;8(7):e68322.

[6] Cell. 2013 Dec 19;155(7):1446-8.

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UHN Staff

University Health News is produced by the award-winning editors and authors of Belvoir Media Group’s Health & Wellness Division. Headquartered in Norwalk, Conn., with editorial offices in Florida, Cleveland, Pittsburgh, … Read More

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