I have made some very surprising, but also very useful discoveries.
First and most of all, neither lysine nor legumes alone appear to be causing symptoms. They do it only in combination with fat, mostly monounsaturated or Omega 3 fats. It looks like I can eat 300g of dried lentils every day as long as I don't combine them with any fat. I can even combine them with fruit. This was hugely surprising to me,
Sadly, my hopes that fat might be the one limiting factor that explains everything have not been confirmed. Fruit along causes symptoms, but only after repeat consumption in higher quantities.
The most important insights summarized succinctly.
*Lysine alone or in combination with other carbs (even acid) doesn't cause symptoms in the absence of fat.
*Fruit does cause symptoms if consumed with several meals in a row in higher quantities.
*The problem in fruit likely is the fruit sugar or a fruit fiber (pectin), NOT the acid content.
*I believe so because (1) apples are especially problematic and contain high fructose, (2) bananas and dates are problematic, but contain no acid, (3) mandarines aren't more problematic than other fruit, but have high acid.
*Drinking 4-6 8 oz glasses of water in the 1-2 hours after a meal appears to help reduce symptoms, possibly because the water-soluble nutrients get absorbed more rapidly and are no longer available for fermentation by the microbiome.
*High insulin spikes appear to be causing symptoms. That can be managed by having smaller meals and make meals in advance and let starchy foods cool down overnight to increase resistant starch.
*Monounsaturated fat causes symptoms alone when consumed in high quantities, but some can be tolerated. It must not be consumed in the same meal (possibly on the same day) as high-lysine foods or fruit. E.g., Guacamole (avo, garlic, salt) with bread is ok. Avo + banana pudding is not.
*It seems to be important to avoid greens, possibly because of the nitrates, though some can be tolerated when eaten in a non-fat meal. Nitrates are reabsorbed in the gut over more than 1 day, so any future fatty meal on the same day or even a day later as the greens might be problematic.
*Most spices I tried (ginger, paprika, chili, black pepper, cinnamon) appear to be problematic no matter what they are being consumed with.
*Cocoa with almond or oat milk sweetened with pureed dates causes very strong symptoms. Jury's still out on cocoa with almond or oat milk sweetened with swerve (erythritol).
*It appears that onions, garlic and cauliflower can be consumed in isolation or added to meals containing no or very low amounts of fat. They are all low in nitrates. There appears to be no difference for garlic and onions raw vs. cooked vs. pre-crushed with wait time (for organosulphur compound production)
*Adding a quarter teaspoon of ground mustard seeds to cruciferous vegetables (e.g., cauliflower) for glucosinolate/sulphoraphane production does NOT cause additional symptoms. (it also does not appear to be particularly helpful)
*Nightshades per se do not appear to be causing symptoms when consumed without fat. In higher amounts, they may be problematic with a high calcium intake.
*Calcium appears to be causing symptoms if it's either very low or very high, so the intake should be calibrated to about 800-900mg a day. That seems to be about the goldilocks zone.
*Green tea appears to be harmful, probably because of the caffeine.
*Omega 3 fats (both long-chain and very long chain) appear to be detrimental in higher quantities no matter what they are combined with. I suspect because they are involved in thyroid hormone metabolism. There are essential so can't be avoided. I am limiting consumption to 1-2 handfuls of walnuts a week. In lower amounts, walnuts are working well, but of course only if not combined with a fat that needs to be separated from fats.