Leaky Gut, or something else entirely?

Autism and Gastrointestinal Symptoms: there is a link, but it's not what you think.

If you're on any of the "free" social media platforms, and you happen to be interested in autism, autistic people, or topics around autism, you may have noticed that the platform regularly delivers up ads in your feed promising "cures" or remediation of "autistic symptoms" by solving the "brain-gut problem." As we head into April and Autism Awareness month, these have been appearing more frequently.

This "link" between autism and "gastrointestinal symptoms" has been a significant line of inquiry in the “academic world” for decades. (It’s also an odd feature of certain strains of evangelical protestantism.) If you search for "autism and gastrointestinal problems" on Google Scholar, you'll find more than 30k entries. Articles like this one (link) from the Journal of Pediatric Gastroenterology and Nutrition (link), tracing the so-called "brain-gut connection,"  have been cited by thousands of authors and researchers in tens of thousands of articles. I point out this article (Autism and gastrointestinal symptoms (Horvath & Perman, 2002)) because it has some very nice graphics to illustrate it's data.

The article begins with a "helpful" disclaimer / introduction to catch the reader up on autism and it's potential link to gut problems. Trigger warning, the introduction is highly reductive and the language has largely fallen out of favor. But, it will help to set up my point and guide the way forward as the attitudes and beliefs that underpin the intro are still around - as evidenced by the recent social media ad campaigns.

"Autism is a collection of behavioral symptoms characterized by dysfunction in social interaction and communication in affected children. It is typically associated with restrictive, repetitive, and stereotypic behavior and manifests within the first 3 years of life. The cause of this disorder is not known. Over the past decade, a significant upswing in research has occurred to examine the biologic basis of autism. Recent clinical studies have revealed a high prevalence of gastrointestinal symptoms, inflammation, and dysfunction in children with autism. Mild to moderate degrees of inflammation were found in both the upper and lower intestinal tract. In addition, decreased sulfation capacity of the liver, pathologic intestinal permeability, increased secretory response to intravenous secretin injection, and decreased digestive enzyme activities were reported in many children with autism. Treatment of digestive problems appears to have positive effects on autistic behavior. These new observations represent only a piece of the unsolved autism “puzzle” and should stimulate more research into the brain–gut connection." [source]

With that, I should share again that I am autistic and non-verbal. I also have a ton of GI "problems." In fact, the data show that most neurodivergent people, regardless of age or gender, have some sort of GI trouble. This article won't attempt to dispute that we have a tendency towards GI problems, it will attempt to explain why.

The problem becomes, and the reason for this article, researchers assume that autism is the reason why we have GI problems; that autism is the "why," that whatever is making me autistic is also making me have GI problems. They think that if they can solve that puzzle, not only can they cure my GI discomfort, but also my autism. Somehow, they posit, this "brain-gut" connection is responsible both for my being autistic and my having GI problems. That's the summation of this line of inquiry.

To that end, when I've shown up in the doctor's office over the years, I've been recommended for all sorts of diagnostic exams. I've had 5 endoscopies - 3 up and 2 down. I've had a radiological study whereby I ate a radioactive sandwich and had a scanner track my digestive pace. I've had CT scans. I've had MRIs. I have all sorts of blood tests. I've answered all manor of questionnaires. It’s been recommended that I go vegetarian, go vegan, eliminate gluten, and - of course - loose weight. I dutifully tried them all. None worked. Through it all, I'm still an autistic person with GI issues.

Moving forward in time to 2012, a group of researchers published "Anxiety, Sensory Over-Responsivity, and Gastrointestinal Problems in Children with Autism Spectrum Disorders" (link).  That paper has spawned over 300 more articles on the subject, including this one, "Autonomic dysfunction in autism: The roles of anxiety, depression, and stress" published recently (link) which provides an amazing quote that perfectly sums up why there's still so much confusion regarding this issue, "Autism spectrum disorder (ASD) is associated with atypical autonomic nervous system (ANS) function. However, little is known about this relationship, while accounting for co-occurring mental health conditions (e.g. anxiety) that are also associated with ANS dysfunction. In addition, research on the ANS has typically involved physiological measurements, without using more clinically meaningful measures of ANS dysfunction, such as the self-reported frequency of ANS related physical health symptoms. Furthermore, very little is known about ANS function in autistic adults, given that previous research has focused on ANS dysfunction in children with ASD." 

Unfortunately, this is how research works - and how slowly it progresses. 20 years after the first inquiry and we're just now getting around to studying autistic adults.

The conclusion of the authors, however, was an "I told you so" moment for me. "Together, we conclude that ANS dysfunction is not a feature of ASD per se, but instead attributable to the high levels of anxiety and stress in autistic adults. We discuss the clinical relevance of these findings for managing ANS dysfunction and other physical and mental health concerns in autistic adulthood."

Did you catch that? It's not your gut biome that is the problem, it's your stress and anxiety that's the problem. If you can manage to solve your anxiety issues, then your gut problems will likely work themselves out. As the authors note, "[a]lthough autistic adults reported greater ANS dysfunction than matched neurotypical controls, this difference was not significant after controlling for anxiety and depression. Similarly, in a large nonclinical sample, we found that anxiety and stress mediated the relationship between autistic traits and ANS dysfunction." Yes, you read that correctly. After controlling for psychological factors, there was no difference between autistics and neurotypicals in terms of GI problems. We both tend to experience these problems for the same reasons and at the same rates. We are, after all, both human.

Let's think about this in a non-clinical way. Anxiety triggers our body's "fight / flight / freeze" response. This is rather well known. When our "fight / flight / freeze" response is triggered, certain systems in our body shut down. Digestion is one of them. After all, who wants to stop to poo when you're being chased by a tiger? Millenia of evolution has given us this advantage of not having to take care of certain bodily functions whilst being threatened with harm.

But, we don't live in the wild any more. For the most part, we're not being chased by wild animals on a regular basis. Nevertheless, we do have a lot of anxiety. (This seems to increase every year, doesn't it?) That anxiety triggers the same shut down in our digestive system. If you're dealing with chronic anxiety, you're likely also dealing with chronic GI problems. I know that I certainly do. It's been such a huge issue with me that I've spent most of my life trying to solve that puzzle. Even now, with a solution in place, I still have problems because my autistic system refuses to let go of anxiety. It seems as if anxiety is it's default state.

So, if you're tempted to shell out hundreds or thousands of dollars on "custom tailored probiotics, hand crafted to match your specific DNA profile," based upon an advert that you found on social media ... don't waste your money. Probiotics can help, but only in certain situations (link). A better bet for your money is to investigate the things that are triggering your anxiety, and invest in reducing those to a minimum.

For me, I have sensory issues. I've had them my whole life. As we know, sensory issues can impact bodily functions like digestion. In my case, I've spent a lifetime trying to figure out why I seemed to always feel sick and tired. I've spent almost a half a century feeling sick and tired of being sick and tired.

As I’ve shared, I've had endoscopies. I've had radiological studies. I've had all sorts of pills. I've had all sorts of nutritional advice. I've been fat, sick, and nearly dead. When a pill's side effects are too much to bear, often another pill was prescribed. There were side effects upon side effects. If you’re autistic, this will likely sound familiar

But, I'm a non-verbal autistic. It has been very difficult communicating just what level of suck I was feeling about a particular pill or diagnostic test. After about a half-million dollars of work, I was done with it all. Several years ago, I was finally in a position in life to be able to change insurance plans from an HMO to a PPO, and thus be able to have more control over my journey to health. This is when I found the right doctor.

I found a clinical nutritionist who understood the autistic body and brain. I was examined from that standpoint. After a few sessions and a few rather non-invasive tests, I discovered that I am histamine intolerant - the root of all of my discomfort and pain. Histamine containing foods can cause inflammation in the body. In my body, it was like having a truck with a flame thrower moving it's way down my digestive path. I was given a new diet to follow - time restricted (to manage my energy / hormone levels and thus sleep better), high-fat / low-carb (to run my body as designed), histamine free diet. Within a few days, I was pain free. Within a few weeks, I was medication free. Within a few months, I had dropped some of the weight that I gained from being on a lot of medication. Now, several years later, I have lost all of the extra weight that I gained through my journey with western medicine and weigh about what I weighed at my high school graduation. I feel great - which is the most important. Plus, all of my blood tests are perfectly normal (hint: most of those scary articles about a high-fat diet killing you are sponsored by big pharma’s push to get everyone on statins).

I share my story with you in order to begin a conversation about nutrition health. I've been given all sorts of "healthy" option lectures and advice from doctors. They all didn't work. Why? Because most doctors have less than 10 hours of nutritional education and are reading from some pamphlet that was sponsored by a group with a financial interest in keeping you in the doctor's office. Histamine intolerance is actually quite common in people who are from families with less than 5 generations living in western societies, eating western foods. It's also common in people with Rh negative blood types. Having a high level of sensitivity, like sensory processing issues, is also a contributing factor. Thus, it's no wonder I'm having problems. All three describe me.

I hope that, in sharing my story, you will find a bit of hope. There are counselors, coaches, and doctors out there that understand you. They understand how you, the autistic person, are designed. They understand how to fuel your body in a way that doesn't leave you fat, sick and in the doctor's office all the time." If you’re having trouble finding one, leave a comment and leverage the power of the community.

Thank you for reading and for your support. If you’d like the full AutSide experience, please subscribe.