Oh that is very interesting!! Substances can be both medicine and poison-could it be because of their ability to hasten biorythyms? this from thiamine research: "To maintain the level B1 near the maximum levels for prolonged periods can cause an acceleration of the biorhythms and therefore produce a potential impulse capable of fostering the growth of preexisting breeding grounds of tumor cells." - Vitamin B1 and Parkinson : The final results of the research carried out by WeAreParky – WeAreParky which is why I prefer starting with small (sometimes very very small) doses.when possible...though potential can go either way!