I ran across that now elderly (and locked) thread that Keith did in which Karen and the struggles to regain her son Jonathan's health were so central. (What was the name of that thread again Karen?)
As Dr Perlmutter pointed out in a recent speech I saw online, more than 80% of everything that has ever been written about the microbiome of the human gut and its connection to our brains has been written in the past five years.
All these concepts tie in together:
Get rid of gluten
Get rid of all other sources of excess (empty) carbs
Get rid of processed junk oils
Get rid of fake additives like MSG and aspartame
Add healthy fat to a diet of abundant fresh produce and adequate protein.
All of these things together work to reduce inflammation. They reduce intestinal permeability and restore the healthy balance of the gut flora.
I don't think any one thing is a "silver bullet".
The original thread was entitled something like "Sunshine & Seizures." (It was later renamed to something like "Gut Brain Connection." It began as a thread about photosensitive seizures by a Mom whose child would have seizures on the beach, I think, from the sun reflecting off the water. I got involved in that thread back in 2012, because in the Fall of that year, Jon started having photosensitive seizures, which was a new thing for him. He'd been completely seizure free for a year on the Keto diet, and then, following a tummy flu, had a severe relapse that went on some months. In addition to his tonic-clonic and tonic seizures, which he'd had before, he started having gelastic seizures (giggling/crying fits -- we didn't even realize they were seizures for a few months) and then tonic seizures that were triggered by photosensitive stuff -- like light reflecting off water, or the TV screen, etc. For months, Jon and I were shut-ins, sheers drawn across the windows, low lights on in the house, no TV or other electronic amusement. We read books a lot and listened to music, and I home-schooled when he was conscious enough to pay attention.
It was Keith, I believe, who alerted me to the gut-brain connection, which certain folks poo-pooed as having no hard science behind it. However, I began to put 2 and 2 together. Jon started having seizures at age 1, and at the same time, he began having chronic diarrhea that he has had most of his life. This was the same time that he was weaned from breast milk, and began eating wheat and other grains in addition to rice. Later, we suspected Celiac disease, because we noted the diarrhea was more severe when we were in the U.S. (on a wheat-based diet) than when living in Asia with a rice-based diet. When he started the Keto diet, the diarrhea cleared up. But then, after the tummy flu, he started having diarrhea again. And seizures.
We had a GI work-up, and the GI doc said Jon had Inflammatory Bowel Disease, but could not suggest a remedy. I consulted with a pediatrician in Thailand, whose specialty was nutrition (and the Keto diet). She said that, due to the tummy flu, Jon's gut was chronically inflamed, and he was not absorbing fats (or meds) properly. Thus, he wasn't getting enough of the important fats from the diet to make it work. So, she worked with us on healing the gut. A very simple diet for a few weeks of foods that were helpful for inflammation and easily digested, a round of probiotics, pancreatic enzymes (to break down fat molecules), and zinc supplement (which helps heal gut). After a few weeks on this regime, the seizures faded away, and within 2 months stopped altogether. And, now, 2 1/2 years later, he remains seizure free.
ETA: I also forgot to add that she put him on MCT oil. She explained that MCT oil is a treatment for people with malabsorbtion syndrome and other bowel diseases like Crohns because the MCT oil is absorbed differently and more efficiently than other fats.