When I wrote that, I wrote it as if I were seriously considering doing those food challenges. Really, though, I'm not at all sure that I would do that unless I were pretty sure that the reactions would be relatively minor. For one thing, if the reactions were likely to be major, then obviously I should be able to prove a sensitivity simply by doing the challenges themselves, one at a time.
In order to build up an antibody level adequate to yield a valid test result, one must ingest an inflammatory food for a significant period of time, because with continued regular exposure to an antigen, antibody levels continue to slowly increase for an indefinite period of time. That implies a significant number of days of reactions, before an adequate antibody level is attained (one that's capable of reliably triggering a positive test result). By comparison, a trial and error testing program requires only a single exposure to an antigen (and possibly a follow-up repeat exposure, in order to verify the result).
When there are multiple minor food sensitivities however, then combinations of inflammatory foods tend to cause a reaction even though the individual foods by themselves, may seem to be well-tolerated. Or dosages may matter. In those situations, obviously the EnteroLab tests should hold a huge advantage over trial and error testing.
Since you recognize that developing a reliable challenge program is pretty much guess work, here are my thoughts:
For an ordinary gluten challenge, doctors recommend the equivalent of 1 or 2 slices of wheat bread, daily, for at least several months. Those who don't understand how insensitive the blood tests actually are, mistakenly recommend as little as a few weeks or so, while those who recognize how difficult it can be to get a positive result on a celiac blood test, tend to recommend a much longer challenge (such as 5 or 6 months or so). But this is because the blood tests are so insensitive and unreliable.
In view of the fact that the EnteroLab stool tests are at least several orders of magnitude more sensitive (and more reliable) than the blood tests, IMO a gluten challenge that lasted for 1 week would probably provide a reliable test result for most people, and a challenge that lasted for 10 days to 2 weeks should provide a reliable test result for even cases where gluten sensitivity is still a minor problem. IMO, the approximate minimum amount of antigen ingested can probably be far less than the equivalent of 1 or 2 slices of wheat bread. After all, most of us are capable of reacting to a few crumbs of bread, so in view of that, just a decent sized morsel should work. An ordinary cracker, for example, should be adequate, IMO. It should certainly be adequate to prepare one for a stool test, at any rate.
The same guideline should work for any other food sensitivities. Since the half-life of most food antibodies is only 1/20 that of gluten (gliadin), it's tempting to think that one could prepare for a stool test by eating the food for only 1/20 the amount of time (which would be less than a day). But as any engineer familiar with designing models can tell you, it doesn't necessarily work that way. Models are affected differently by virtually all of the physical influences of various parameters when compared with full-size objects, and that probably applies in this case, also, even though we're not actually talking about physical models here.
Anyway, with that in mind, I'm inclined to believe that somewhere between 1 and 2 weeks of food challenges, using approximately (at least) tablespoon-size dosages, should be adequate for preparing for an EnteroLab stool test in situations where the food being tested hasn't been eaten in a (relatively) long time. A single dose each day might be adequate, but an additional daily dose or 2 would probably help to boost the antibody level for a more definitive test result.
Or, I could be all wet.
Tex