Any history of mild hypoglycemia where you are less clear-headed and less patient in between meals?
My understanding is that the body needs cortisol to properly utilize branch chain amino acids. BCAAs are among the supplements that athletes use to build muscle.
I think the AAs in muscle get converted by the liver to glucose to fuel the brain, etc, but cortisol is important in this process.
Do you like the effect of some glutamine between meals, maybe along with some B6?
Do you now have in increase in fatigue after a stressful day?