It took a reading a few thousand pages of ncbi.nlm.nih.gov papers over a number of years (I made it a habit just to try to crack this thing), this is one of those traditional 'fall through the cracks' kinds of things. My PCP admitted to me that she felt ashamed at not being able to help any further and not knowing what to do, and she's internal medicine.

I have reactions to nearly every food group out there, even things traditionally safe for many (minus the ultra safe things like rice, lamb, etc).

It's definitely not a digestion/absorption issue, in fact I probably have barrier permeability issues as things like taking GABA will result in respiratory depression + temporary oxygen starvation for a few seconds followed by that emergency contraction of blood vessels that the body does when trying to get oxygen to muscles. That's one good indicator of systemic barrier dysfunction, for example, as that is certainly not supposed to happen in healthy people (though I wonder if one tiny benefit is making GABA slightly more effective for me for anxiety over, say, the average person due to potentially-increased BBB permeability). Additionally, things like P-glycoprotein inhibitors (like piperine, etc) cause me to react much more strongly to food/environmental things.

Apples would contain, say, the most pyruvate and malic acid (though I react to apples pretty badly, sadly, I'll get arthritis-like symptoms (which makes typing and manipulating objects difficult, for example), though I take an OTC 5-LOX inhibitor nowadays that is actually surprisingly quite effective at preventing things like that from happening in accidental food exposures. Still not enough to have apples straight though, lol.

So it's things like that. Most of this is things like looking at the Krebs cycle, finding upstream things to targets that I want that seem to perform well (like oxaloacetate, which is sold at an outrageous price), and then putting them through the empirical test pipeline to see if they hold up.

Things like niacinamide for example I'm taking 1.5-2. grams a day which would be hard to get from food, pyruvate is also hard to get from food as well. I love the idea of food as medicine, but unfortunately it's mostly calories in (and thankfully I don't seem to react to multivitamins, thank God).

I've tried several thousands of dollars worth of supplements over the last several years trying to find combinations that work. This is most certainly harder than most of the machine learning problems that I work on, as the loss signal is not all that clear, really (unfortunately)!

I am glad to have found something that seems to have a positive impact, however!