The table lists grain proteins.
Stomach acids digest proteins into amino acids when the acid is strong enough to activate the pepsin.
When the system fails partially digested protein chunks wreak havoc on intestines.
So any protein, fish, fowl, grain, legume and all can become a problem if not properly digested.
So salt food to taste to insure enough stomach acid is made and don't dilute it before you use it (eat).
Carbonated beverages are the worst.
But I agree, all sorts of grain proteins can be a problem. What may be true for most may not be true for everybody. It's a good thing to remember.
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