Good thinking. Since one of my problems was cortisol resistance. So it's not like only insulin can trigger resistance in high doses. My stressed system was giving my body all the symptoms of low cortisol; so when I discovered my cortisol tested high, it was a puzzle... until I found out about cortisol resistance, which I fixed with circadian rhythms reset techniques from Dr. Kruse.

And norepinephrine and adrenaline (epinephrine) are both hormones which act as neurotransmitters, too.

Still, I am responding so well to niacin, an amino acid that contributes to the creation of neurotransmitters, I think I am dealing with a failure in the supply chain. Without a good diet, we don't eat enough protein to make what we need. With sugar and wheat actually blocking the nutrients to make neurotransmitters, we are undercutting production that way, too. Which is how diet fixes things, certainly; many many people report better mood with low carb. Because they are finally making enough neurotransmitters.

Julia Ross's book, The Mood Cure, has a saga about how Prozac was being undercut by the amino acid tryptophan. Which worked better.