Just to play devil’s advocate, isn’t it also possible that the preference for a monotonous diet is driven by gut makeup?
The theories for how gut-brain axis modulation works include altering the balance of nutrients that get absorbed and modulating the vagus nerve, primarily. For someone with autism it might be possible that altering some of these balances could make the condition better or worse, but that’s all theory without much foundation.
What is known, however, is that diet has a massive impact on the microbiome. Even the mechanism for that is obvious: Bacteria thrive on different foods, so if you eat more of one class of nutrients and less of another then the microbiome proportions will adjust based on which ones thrive on that diet.
- what all studies show is some vague "craving" for something generic, e.g. the link between iron deficiency and craving for ice
- but what you see in autists is often a far stronger effect and not just for eating something, but also against eating most other food. A craving for chocolate does not remove appetite and willingness to eat other food. It just makes you really want to eat chocolate.
- more important the way autistic people get fixated on a monotonous diet is far more specific then any effects we have observed from gut bacteria or other similar sources AFIK. Like lets say your gut bacteria might make you crave fish. You autism on the other hand might make you crave dino formed fish sticks with a specific texture. And there is just no way gut bacteria care about your fish sticks being dino formed or the specific texture of them... But a autistic person often does care, quite a bit even.
1) Eating the same food frequently means I don't have to spend any of my cognitive cycles on deciding what to eat.
2) I know that this food will sit alright with my digestive system. Everyone I know personally on the spectrum has stress-related digestive issues.
For snacks and small meals I will eat citrus or microwave a small sweet potato and this helps with Vitamin C.
Autistic adults are not children and using dino-shaped fish sticks probably does not represent most adults on the spectrum.
They didn’t run any experiments trying to change the diet or microbiome. They just correlated dietary preferences with some markers that might be correlated with the microbiome.
The paper does not say anything about how changing the microbiome might change preferences. The simplest and most well tested explanation is that dietary preference are driving the microbiome.
There’s a lot of woo-woo microbiome discussion out there that misses the really obvious basics of how the microbiome comes to exist and thrive: What you eat is what the microbiome eats, so changing what you eat will change the composition of bacteria that thrive. People who prefer chocolate are correlated with people who prefer sweet diets. High sugar intake is proven to alter the microbiome.
It measured some bio markers and some dietary preferences and claims some correlation.
The correlation is that what you eat fuels the microbiome. So your diet influences the microbiome by fueling or starving different bacteria.
Complex theories about causality going the other way through complex chains of flavonoids to bacteria to neurotransmitters to the parasympathetic nervous system sound impressive with all of the big words, but it’s such a complex theory that would need other testing to even begin to understand if there was something there.
Testing the other direction is easy and obvious. You can grow many bacteria in a Petri dish and see that some grow better or worse with different nutrients.
What's the theory now? I didn't propose any specific theory -- just noted a mechanism of influence.
I am forced into an extremely limited diet to avoid provoking my body any more than I have to. And, notably, one of the first reactions used to be something not tasting as good as it used to (or in one case tasting worse than it had.) It doesn't always happen but when it does it's a near 100% accurate test--the only time it ever fooled me the actual culprit turned out to be something my wife put on her face.
I saw what happened to my mother (very similar path, but started much later in life), I already knew how to isolate what was giving me trouble before it ever happened. Most people don't, though, especially when dealing with things where it isn't high on the ingredients list (or, sometimes, not at all--they are strong about requiring manufacturers to list what they put in, but there is no such requirement about noting what they fail to take out from a natural source. Not to mention being allowed to specify that most evil of ingredients "artificial flavors". The second most evil being "natural flavors.")
They never successfully identified what happened. Just diagnosed it generally as failure to thrive.
Case reports are unreliable due to placebo effect.
The antifungal myth has been tested by too many well-meaning parents with no results.
to stop pulling levers when they are not enjoying their time,
is medical injustice.
How long ago was it you were in threads calling the treatment method in TFA an unfounded crackpot myth?
often allowing the body to get a good run at any low-level chronic infections which have nested and protected themselves,
able to leave the biofilmed region and wreak havoc - even if only intermittently.
Very interesting, this impact of antifungals on longterm bacterial infections! Specifically known to be effective off-label for Bartonella.
which for many is not the case for a variety of social economic or behavioral reasons. Add in with explosions of bacterial populations due to alcohol or sugar and you can see how we can change our gut biome drastically from week to week.
Observing that if you eat/drink something specific then you get the shits is valid. Concluding that it is due to a specific mechanism is not valid unless you have something objective like a test supporting that.
It’s like if your train is late and you just conclude that it must be because the steam condenser’s gasket is leaking based on nothing. Maybe true, or maybe the conductor broke his leg, or there is a signaling failure.
Why do you need to know what the mechanism is to avoid mistakes? - if something fucks you, don’t do it.
Encourage others to do the same.
Not a controversial take!
“But what if it’s a big hoax and we create solid stools for nothing?”
This demand for peer-reviewed evidence in place of observation of known and basic mechanisms is out of control.
where you’d have to reply to “well-understood and basic mechanisms” being ignored.
Including the ones we know inhibit a healthy diverse microbiome!
Sticking with your chosen example:
If you lean an anvil on your foot, and start suffering from poor circulation or discoloration of the foot, remove the anvil.
Also, this bit is a non-factual read (don’t put words in my mouth, mate, I choose them carefully).
An uncharitable, bad-faith interpretation at best.
autists have often a much much stronger need for habits and avoidance of change. This includes a change of, or a less repeting/habitual diet. The effect if applified due to autism being commonly comorbid with ADHD and hyper fixation on specific foods being a very common thing (not (mainly) caused by gut bacteria as the effect is too strong and too specific to be "just" a preference caused by gut bacteria)
but this can lead to a imbalance of gut bacteria and that can have an reinforcing effect on wanting a even more monotonous diet, but in the end this is AFIK "just" a secondary reinforcing reason not the root cause
just to play devil's advocate that it isn't an opposing possibility