Food mold, particularly ergot,
has the opposite effect of
niacin. Brain blood vessels are
made narrower, cutting down
the oxygen supply. Ergot is a
common contaminant of grains:
don't provide rye or
pumpernickel breads or crackers.
In short if you keep flushing on the same dose then the blood vessels are collapsing due to mold a few minutes after the Niacin wears off.