As an autistic person with a severe gut disorder (ulcerative colitis - one of the risk factors is a diet high in processed foods) I think it’s very likely that autism causes gut issues, including microbiome issues. If you eat mostly the same foods, the bacteria that don’t feed off them will die off, and you get a less diverse, weaker microbiome. I’m not a microbiologist but I have personal experience here because my UC forces me to restrict my diet in strange ways when I have active inflammation (like for months or years), but I can later reintroduce foods, but then they’re harder to digest for a while because my microbiome has changed. So it makes sense that since most autistic people have more limited diets due to routine, obsession, or sensory issues, we would tend to have worse gut microbiomes.

People who view autism as a disease that might be curable will see any connection as a potential cause, even though in most cases the causal relationship is more likely to be in the other direction. It’s so frustrating.

What’s more, in recent years, researchers have begun to find links between the makeup of microbes that call our guts home and neurodevelopmental disorders, like ASD.

Nevertheless, this connection isn’t always consistent, and some experts have argued it isn’t gut bacteria that trigger ASD, necessarily; it could be that kids with autism are more likely to restrict their diets because of ‘picky’ eating, which in turn influences the kinds of bacteria that persist in the digestive tract.

I’m not a scientist but diet and microbiome changes being a symptom of ASD seems more plausible than the other way around IMO.

The way I read it is we now know what we knew but don’t know anymore. The only concerning line is “potential treatments” I’m AuDHD and even though I have difficulty in certain things in my life I wouldn’t change them to be more NT.