Episode 278 — Gut Toxins Drive AUTISM Symptoms
Guest: Dr. James Adams • Date: October 23, 2025
Episode Overview
This week’s conversation is with Dr. James B. Adams, one of the most respected researchers in the autism community. Together, we explore the powerful connection between gut health and autism and how new tools can give parents answers they’ve been searching for.
About Dr. James Adams
James B. Adams, Ph.D., is the Director of the Autism/Asperger’s Research Program at Arizona State University. His research focuses on the medical causes of autism and how to treat and prevent it, including nutrition, oxidative stress, gut bacteria, microbiota transplant, probiotics, toxic metals, and seizures. He has extensively researched prenatal supplements to reduce pregnancy complications and infant health problems and developed the first prenatal supplement tailored for each trimester. He has published over 180 peer-reviewed articles, including over 70 on autism. Dr. Adams is the President of the Autism Nutrition Research Center, Autism Diagnostics, and Gut-Brain-Axis Therapeutics, and chairs the Scientific Advisory Board of the Neurological Health Foundation. He is also the father of an adult daughter with autism.
You’ll Discover
Why Gut Problems Often Begin In Infancy (3:15)
How Harmful Bacteria and Yeast Create Powerful Toxins (5:40)
The Surprising Link Between Toxins and Key Neurotransmitters (6:22)
What The New Urine Test Reveals What Other Tests Miss (12:44)
Why Addressing Constipation is a Critical Step to Lowering Toxin Levels (15:07)
Referenced in This Episode
Gut Toxin Test → analutos.com
Gut-Brain Axis Therapeutics → gbat.com
Autism Nutrition Research Center → autismnutritionresearchcenter.org
Full Transcript
Len Arcuri (00:02.206)
Hello and welcome to Autism Parenting Secrets. You already know that the gut is important. But what you may not know is that toxic chemicals from harmful gut microbes can play a major role in many of the symptoms linked with autism. My guest is Dr. James B. Adams, Director of the Autism Asperger's Research Program at Arizona State University. He's published over 180 scientific papers, including more than 70 on autism.
His work covers nutrition, gut health, toxins, seizures, and prenatal supplements. He also leads the Autism Nutrition Research Center and other groups focused on gut brain science. And he's the father of an adult daughter with autism. Dr. Adams and his team have developed a new test that spots harmful gut toxins with striking accuracy. This could change how we understand and treat autism. The secret this week is...
Gut Toxins Drive Autism Symptoms. Welcome Dr. Adams. Well, I guess I'm always excited when I have guests, particularly ones who have your notoriety and you have a special place in my journey because you were the very first presentation I ever saw at an autism conference, my very first conference, 2009 in San Diego. And you were the very first person I saw.
James Adams (01:08.45)
Thanks very much, Len.
Len Arcuri (01:30.536)
presenting. So again, I appreciate that it was you because you provided a very measured and very reassuring information as somebody who is totally new and definitely in fight or flight after my son's diagnosis. So I thank you for that presentation and I've seen you at many conferences and I will ever since then, you you've been constantly out there helping to find answers and to serve parents who are on a similar journey. So I just want to thank you for the work that you do.
James Adams (02:00.342)
Well, thanks, Flynn. Glad to be helpful to you and hopefully many other families.
Len Arcuri (02:04.924)
Wonderful. Well, we finally got to meet again at the MAPS conference a few weeks ago. And I know you there were giving a presentation and I touched on the new test that you developed. So for our listeners, feel free to provide any backstory if you'd like, but otherwise I'm excited for you to share the new insights that you've gleaned that have resulted in what you're offering now to parents.
James Adams (02:32.238)
Sure. So we've known for many years that many children and adults with autism have chronic up problems. Our research suggests they almost always begin in infancy. That's something that's not well known. Even adults who have GI problems in their 20s, 30s, 40s, 50s, they've told us those GI symptoms began in infancy and just kept on going. Very difficult to treat. And that's about 40 % of children and adults with autism.
But what we've now learned, it's actually most children with autism have substantial gut problems, sometimes obvious with symptoms of constipation, diarrhea, bloating, abdominal pain, but half the time hidden. The only symptom is worse autism symptoms. And so what we've discovered is that most children with autism have some very harmful bacteria or yeast in their gut, producing some very harmful toxins.
There have been hints of this for many years. For example, 17 papers on one toxin, P. creosol, made by about 50 different bacteria. And 17 studies, every one of them agrees the level of this toxin is higher in children with autism. And about 20 % of them have high levels of that particular toxin. Four animal studies show if you give that toxin to mice, it causes autistic symptoms in the mice.
One of those studies shows if you then give the mice, the mouse, a fecal transplant from a healthy mouse, they recover. They lose their autism symptoms and begin developing normally. So it was just a major clue that this can, if it can cause autistic symptoms in mice and it's present in higher levels in a subset of children with autism and the higher the level, there's a correlation with worse autism, then it's pretty clear it's contributing to autism symptoms.
But there are now, we've identified 40 papers which have reported on levels of eight different toxins in children with autism. And we've have gone on to more than double that number and developed a test to measure the level of many toxins from gut bacteria and yeast in kids with autism. And so we found that 90 % of kids with autism have extremely high levels of one or more. And by extremely high, I mean higher than that.
James Adams (04:58.838)
of any typical child, sometimes 10, 100, even 1,000 times that of the average level in a typical child. Some of these are yeast toxins, some of them are bacterial toxins. But what all the bacterial toxins have in common is they alter two amino acids that go on to make either dopamine or serotonin. So basically they make corrupted versions of serotonin or dopamine.
And those are important neurotransmitters in the brain. They have a big effect on mood, on learning, on cognition. Serotonin goes on to make melatonin, which is very important for regulating sleep. So we know that these corrupted versions interfere with the general metabolism of those neurotransmitters. And we believe are contributing quite a bit to different autism symptoms.
And so we've developed a simple urine test where we measure not one, but about 17 different toxins that are commonly elevated in children with autism. we just yesterday submitted our paper on this. So the paper should hopefully be available as a pre-print in a few days. And then it will be reviewed, go under peer review, and then hopefully be published in a few months. But I've already spoken on it quite a bit.
And the bottom line is that most children with autism have several of these metabolites. It's very different from one child to another. That's because it's a very different gut bacteria. But again, what they all have in common is they make corrupted versions of dopamine or serotonin that affect the brain. So we found a few kids who did not have those. And those very few children with autism had other major inborn errors of metabolism. So I'd say it seems at about 10 %
of the kids that we've evaluated seem to have a major genetic disorder, but about 90 % of kids with autism have major gut dysbiosis, which is treatable.
Len Arcuri (07:08.875)
Fantastic. Well, I appreciate that detailed take. And when you talk about dysbiosis, I know most listeners are going to be familiar with that, but we're talking about this gut imbalance, right? Which ultimately can create a lot of issues. And I'm guessing leaky gut also is related to that, right? Because I know my son's got lots of allergies and definitely related to gut issues and leaky gut. So with
James Adams (07:32.27)
you
Len Arcuri (07:35.804)
respect to dysbiosis and that imbalance being a key root cause or a core issue to focus on. Can you explain a little bit in terms of these toxins, how did they get there? So for somebody just wanting to understand, okay, if this is what's happening with my child, what's the source? where did it originate? Can you talk a little bit about what might have contributed to this state?
James Adams (08:00.366)
Yeah, so we have a lot to learn about it, but just a little background. You have about 500 species of bacteria in your gut, typically. And a major meta-analysis of many studies, including a couple of our studies, showed that kids with autism as a group have higher levels of about 500 species and lower levels of about 100. So when we talk about dysbiosis, we mean high levels of some bacteria, higher than normal.
often harmful ones, and a lack of beneficial bacteria. So a good way of thinking about it is it's like a village. In the village, you might have a policeman, a teacher, a cook, a farmer, but if everyone's a farmer, that's not gonna be so good. If everyone's a doctor, that's not so good. You need a wide diversity of gut bacteria to perform all the functions you need in your gut. So this, one of these,
metabolites I mentioned, P. creasol, we know the most about it. We know that it acts as an antibiotic in the gut. It kills off the competition. But it also damages the gut, causing increased intestinal permeability or leaky gut. So that the toxins made in the gut leak out of the gut. So it has many other functions. It also attacks the mitochondria. So the mitochondria produce less energy.
the body and brain and increased oxidative stress, which is again very common in autism. And so by affecting the mitochondria, they're affecting every cell, almost every cell and every organ in the body. So just widespread effect. So it's way beyond just the neurotransmitters. It also affects kidney function. This toxin P-creosal is known as a nephrotoxin. In people with chronic kidney disease, the more of it you have,
the shorter you have left to live. Cannot be removed by kidney dialysis. And so, unfortunately, kids with autism are at higher risk as adults of chronic kidney disease. They're also at higher risk of Parkinson's disease, and Parkinson's involves the disruption of dopamine. People with Parkinson's have eight times higher the level of P-Cresol in their brain, in their cerebral spinal fluid, compared to typical people.
James Adams (10:26.53)
So it's not just autism, affects these other conditions as well. But basically, so the bottom line is there are hundreds of species of bacteria in the gut. It's very complex. Any one metabolite like P. creosol, we know over 50 bacteria can make it. But the yeast metabolites seem to be different. In our study, we published a year ago, and in some previous work we had done, we found yeast metabolites don't affect gut function.
but what they do affect is brain function. So in the same way, a good analogy is alcohol, because alcohol is also a yeast toxin. And so when alcohol gets into the body and the brain, it affects your ability to think clearly. It affects your cognition. At high levels, your language might slur. It's harder to talk. Your coordination gets impaired. Your emotion regulation is impaired. But you don't have gut problems. And so...
Simple way to phrase it, a simple summary I leave with parents is that most kids with autism are drunk on the toxic metabolites from their gut with toxins that are 100 more times potent than alcohol and that we know cause autistic symptoms in mice and we know contribute to disrupted function in the body, in many organs and almost every cell in the body.
Len Arcuri (11:52.446)
Great. Now that's powerful. In terms of the test that you've now available to identify this prior test, like urine tests, like the organic acids tests and other tests that people may do, would not be picking this up.
James Adams (12:05.698)
Right, our test is just much more extensive. We've identified many toxic metabolites, never measured before in autism. And so our test, we're pleased to say, is now commercially available from a lab we've been working with for several years. It's a lab in the United Kingdom called Aniludos. The nice thing is the test is available worldwide. Anyone virtually anywhere in the world can go to their website, order the test, doesn't need a physician.
and then have the kit sent to them. They have a special deal with FedEx, so it can be shipped to the parents' home. Just pee in a cup, send the sample back, and in a couple weeks, you get an answer. Do you have high metabolites? And what's really useful is it tells you, are they yeast metabolites or bacterial metabolites? Is it one? Is it five? We've seen up to 10. And how high are they? Are they 10 times normal? 100 times normal?
a thousand times normal. So it gives you an idea of both which type of metabolite they have and how severe the dysbiosis is. And so for yeast infections, we know what to do. We know there are a variety of antifungals that can be used, both prescription and non-prescription. And also, unfortunately, those often don't last very long unless you couple them with a low carb diet. Without going into a lot of detail, basically the yeast, we've
showed in a paper we published 15 years ago when yeast levels are high they the level of your major defense against intestinal yeast and bacteria is low. There's a substance called secretory IgA it's the body's main defense against infections in the gut and when people have high levels of yeast and what we found they have low levels of secretory IgA because yeast have evolved for millennia to excrete an enzyme that destroys
specifically destroys secretory IgA. So that gets back again to part of the reason why these infections are there. The bacterial infections are harder to treat. There's a talk on my website that talks more about that. But if you want, I can briefly mention some of the main things. So one of the basic things to think about is that the bacteria in your gut are constantly making new toxins. So like with a bottle of wine, the longer it ferments,
Len Arcuri (14:16.957)
Yeah, please.
James Adams (14:29.292)
more alcohol is produced, the longer that food or stool stays in your gut, in your intestines, the more fermentation takes place. So one of the first steps to do is just try to reduce the constipation. We have kids in our studies who have not have a bowel movement once every 10 days, once every 12 days. And so the longer they stay in there, the more toxins will be produced. So that's one of the first things to do is try to promote constipation.
They try to relieve constipation. But also changing diet may be able to help. We published a report on 12 different diets that can help in different ways. But different people have different needs. So just trying different diets that help promote motility. Things with high fiber, prune juice is great for that. But high fiber foods, basically fruits, vegetables, whole grains, legumes or beans, those are all good.
Standard medications like Neuralax or magnesium citrate can help with constipation. I'm not thrilled with them, but again, temporarily, they can be helpful.
Len Arcuri (15:37.918)
So I was going to say even with Miralax and PEG, even with the concerns there, you're saying if it's to relieve constipation, you would say it's not an ideal option, but the key is to relieve constipation.
James Adams (15:50.253)
The key is to have a bowel movement every day or even once for each meal. And so I'd prefer to use more natural approaches like magnesium citrate. But again, there multiple laxatives or stool softeners that can be used. I prefer to avoid enemas unless there's an emergency, like someone hasn't had a bowel movement for 10 days. But moving beyond there, there have been many studies of probiotics.
Unfortunately, the meta-analysis of probiotics for autism shows that on average, they have no effect on GI problems, sad to say. They have maybe a very small effect on autism symptoms, but again, just small. I won't say that's true of every probiotic. There was a slightly greater benefit for those that were multi-strain probiotics. But again, remember, people with autism have, you
Typically, 100 plus bacteria that are abnormal and probiotics contain only one to 10 strains typically, and then generally aerobic strains, whereas most of your gut bacteria are anaerobic. So just the wrong thing. Using nutritional supplements, vitamin and mineral supplements to help the body can be helpful. We published a study on our vitamin mineral supplement, several studies showing it helps to some extent with gut issues, but more just overall functioning.
And then the big guns come to our work with microbiota transplant. What we've shown in our first study, the microbiota transplant, we could reduce levels of P-creosol down to normal. We get rid of the harmful bacteria. And what we've shown is the new bacteria that come in are those that produce butyrate. And I should probably explain a little bit. Butyrate is the major food for the cells that line the gut. That it provides 60 to 70 % of the energy.
for the cells that line the gut, about 5 % of the energy for the whole body and brain. And butyrate comes from fiber. Most Americans don't get nearly enough fiber. So can be on a gluten-free diet, but often gluten-free diets are low fiber diets. And so they're not getting enough fiber, so the cells that line the gut are literally starving. And low fiber is probably a big part of the reason why so many people have got problems. But the fiber doesn't seem to help.
Len Arcuri (18:00.818)
Mm-hmm.
James Adams (18:15.094)
Once those infections are set in, it's very hard to get rid of them. Antibiotics generally worsen symptoms. There's a study 25 years ago that inspired us using vancomycin, powerful antibiotic. They used it for 10 weeks. Great improvement in gut symptoms, great improvement in autism symptoms. And when they stopped, even with standard probiotics afterwards, in a few weeks, the benefits were pretty much all gone.
And so, according to a major survey by the Autism Research Institute of 25,000 families, antibiotics are much more likely to worsen symptoms than to improve symptoms. So again, we don't recommend antibiotics unless under very exceptional circumstances. It's actually just the reverse. We think overuse of antibiotics during infancy is a risk factor for autism. So there many things that led to these problems. Low fiber diet.
high antibiotic use, C-section birth, because during a C-section and the mother is receiving antibiotics, they pass on to the infant as well, and they don't get the natural vaginal and fecal microbiota if they're through a C-section birth. And then mother's milk is so incredibly important during infancy for feeding healthy gut bacteria. And unfortunately, at least in our
pilot studies, kids with autism we found have nursed much shorter periods. Notice that because of the autism, they don't bond as well, so it's harder to nurse. It's hard to say. But anyways, that's kind of a quick rundown on some of the treatments that we think are reasonable. I should mention microbiota transplant is still investigational. we've completed four clinical trials. We're doing two more. We have one big phase three, hopefully down the way if we can raise the money for it.
Len Arcuri (19:53.97)
Right.
James Adams (20:13.379)
but it's still only available through research studies like ours.
Len Arcuri (20:17.53)
I was going to say that's not so I remember hearing about that in 2009 and being kind of excited about that possibility. But right now for a parent who wants to go down that road right now, there's really no publicly available option. It's just through research studies, but that may be changing, correct?
James Adams (20:34.274)
We're doing our best to hopefully get it approved. We've worked with a group of kids with Pitt-Hopkins, a very rare disorder. We hope to have it approved for Pitt-Hopkins in one to two years, but autism is probably three to four years away still.
Len Arcuri (20:48.176)
Okay. But in the meantime, I'm guessing that's where your tests can help identify what might help. And if the fecal transplant isn't an option, would be like taking a supplement with butyrate, would that be part of the equation to help basically ward off these toxins? Is that part of the protocol?
James Adams (21:08.398)
Well, I guess I didn't quite answer the question of where the toxins come from. So let me come back to that. So the gut bacteria and yeast make the toxins from the food we eat. Specifically, they make it from the protein that we eat. The protein is a large molecule and it's broken down into individual amino acids normally in the gut. In kids with autism, there seem to be more of these bacteria and yeast.
that then compete and convert those three specific amino acids, phenylalanine, tyrosine, and tryptophan. They convert those directly into these toxic metabolites, then interfere with the others that are chemically very, very similar. So for example, one of them is so similar to dopamine that it blocks an enzyme that converts dopamine to the next step, noradrenaline and then adrenaline.
So it poisons that enzyme because it's very similar but different. So it latches onto the enzyme and then the enzyme stops working. So then you end up with lots of dopamine and not enough adrenaline and that can lead to Parkinson's issues. So they come from the protein that we eat, but we need the protein. We need protein to make many things in our body. And so one option is to consider digestive enzymes.
There's not been very much work on that, but there was a promising study by a company called Curemark where they investigated their digestive enzyme and seemed to have a small effect in decreasing irritability. That was an enzyme specifically tailored to go after protein. But also there have been studies showing many people with autism have problems with digesting carbohydrates as well, especially lactase, the sugar and milk. So a general digestive enzyme for protein.
or proteases, for carbohydrates, and perhaps for fats or lipases, probably would be useful. We did one study of it, seemed to have some help, but a lot more research is needed. But basically, if you're consuming protein, these toxins will be made by the gut bacteria if your body isn't digesting the protein. Or even if it is, some of it will get down into the bacteria to make it.
Len Arcuri (23:32.818)
Got it. So the source is the food we're eating. There's nothing in terms of in utero, something in the past. There's no environmental, other environmental toxins that are driving this. It's purely from the food.
James Adams (23:45.303)
Yeah, I won't say there aren't certainly other environmental toxins that affect people. All I can say is that 90 % of kids with autism have these particular, have extremely high levels of one or more of these. And that it seems very likely they're contributing to symptoms.
Len Arcuri (24:04.53)
Got it. And can you go a little bit deeper in terms of the specific types of symptoms that they're related to or is it just across the board? It can manifest as any of the many symptoms that we're familiar with. Can you talk a little bit about that?
James Adams (24:19.48)
Yeah, so it's complicated to say because the studies that are done by administering them to animals, we can see what effect they have on animals. And so they cause the major symptoms of autism. They cause socialization problems. They cause repetitive behaviors. Again, mice don't talk per se, but they do interact with one another. But in humans, we see...
we can look at correlations with some of these metabolites. But again, there are 17 that we're measuring and many of them, we just don't have the research to say this one specifically causes this. But they're structurally so similar, the best way to think about it is they're interfering with serotonin and dopamine function and melatonin. So for example, we know of order three quarters of people with autism have sleep issues, melatonin sometimes helps somewhat, but
a big part of the issue seems to be the production of melatonin. So we believe that there are probably corrupted versions of melatonin being created from these corrupted versions of the amino acid precursors and the corrupted versions of serotonin. So also just coming back to serotonin and dopamine, again, they are very important in our mood. So with our microbiota transplant studies, we see improvement in many
mood-related symptoms, so in anxiety, in attention deficit or hyperactivity, in depression, in irritability, and a little bit later, cognition. And so those are the types of symptoms that are affected. Most commonly, just parents tell us the child's much happier after a microbiota transplant. And dopamine, serotonin certainly have a big effect on your
overall happiness. So I would say that probably most of the symptoms of autism are going to be affected by that. We also are very suspect that they contribute to seizures. Some of these neurotransmitters can cause seizures and autism. There was one small study of people with epilepsy, not autism, but just epilepsy, and they had higher levels of P. creosal, even higher than the autism group. So as we continue with our research,
James Adams (26:43.33)
We hope to also investigate people with autism who have seizures, and I suspect that they may have even higher levels of these metabolites. 80 % of the time, we don't know what the cause of the seizure is, and this seems like one of the most likely, it seems like a likely mechanism. Again, until we do the research, we can't say for sure, but stay tuned. mean, what we hope to do with analogos is very soon write a, a research study where we invite.
Len Arcuri (27:01.276)
Yeah, that one.
James Adams (27:12.748)
not require, but invite every family who contributes a urine sample to tell us about their child's symptoms. And that way then we can look, okay, this part, these group of people had epilepsy and autism. Do they have other specific symptoms? So we're also just planning a research study right now to look at children with bipolar disorder, with depression, with anxiety, with ADHD. We suspect, we don't know, but we suspect that
Some of those children also have these abnormal metabolites, but no one's researched it yet. So that's why we're going to go look at those groups as well.
Len Arcuri (27:51.006)
All right, great. No, that's extremely exciting. And I think again, with this particular test, I know my son's 18 now and I'm constantly looking for ways of assessing, hey, what's going on and what might be holding him back? So you've opened up a totally new avenue. And again, I think with a simple urine test, it sounds like you can get some really, really useful information where again, the actions that you might be able to take to help aren't
super complex in many cases, right? It may reaffirm some of the diet changes maybe that you might be on the fence with, or sometimes the simple supplements can really help. But my guess is your test helps guide parents with that.
James Adams (28:31.65)
Yeah, I think one of the key things just most parents aren't aware is that there are now five studies including a couple by ours by showing that of order 25 to 50 percent of kids with autism have a hidden yeast infection. The only symptom seems to be worse autism symptoms. And so I think it's so important that every child have a test for that. If not ours, there are some other types of tests you could use, but we think ours is especially good because
we're looking at what's coming out in the urine. And if it was in the urine, it leaked out of the gut into the body. So it's not a question of just what's created in the gut, it's a question of what leaks out of there to get into the brain. And that's why think a urine test makes a lot of sense. It's also just so simple.
Len Arcuri (29:19.058)
It truly is. So, yeah, for people who are listening, and again, I'll include everything in the show notes, but where can they go to learn more? What's the best place for them to find out more about the test as well as all the other work that you're doing?
James Adams (29:31.148)
Yeah, so Analudos is the name of our company in the UK we work with. So the website is just Analudos, A-N-A-L-U-T-O-S. So kind of like analyze, so analudos.com. For information on the treatment side, we have a couple mini videos on our website. It's called gbat.com, G-B-A-T for gut brain.
Axis Therapeutics, gbat.com. So there are some mini videos there about standard treatments and more advanced treatments for gut issues. After doing the analudos test, we have through our nonprofit, the Autism Nutrition Research Center, we have consultants who for $40 for a half hour, we try to keep it inexpensive. They can help interpret and offer
ideas on treatment options. They can help educate families. They're not physicians, but they can educate families about what treatment options they might want to consider based on the test results that they have. So those are, I think, some of the best things. Everyone who gets an analog test also gets a suggestion to speak with those consultants if they don't have their own expert physician. There's certainly many expert physicians. You and I were just at the MAPS conference.
And MAPS again is a great place where physicians get training and especially the MAPS fellows who have been through more training or the MAPS speakers, probably some of the most knowledgeable.
Len Arcuri (31:07.986)
Right. Yeah, no, in terms of parent, if you're listening and again, who is your main medical guide? The population of MAPS doctors are a great place to start to find that right practitioner. And my guess is even those MAPS practitioners, what you've talked about this test and this different way of looking at what's happening is new to them too. So if you're working with a practitioner to make them aware of this, don't be surprised if they're not already. And Dr. Adams, you've been at the forefront.
of research in this space for so long. So again, I thank you for sharing all this and I'm excited to hear excited to hear where you're going and where the future breakthroughs may be coming. again, I appreciate you sharing this now.
James Adams (31:50.594)
Yeah, thanks very much, Len.
