Another thing to keep in mind is the gut/brain axis which has been studied extensively. When you are having a bad head day then likely it is coming from the gut.
I find a great help in neutralizing the acids in the gut by adding some alkalinity (baking soda). Acidity comes from the strong oxides that the immune system produces due to activation. Bulk charcoal is a godsend for me since it sweeps out the junk quite effectively.