This was just on 'Histories Mysteries' on guess which channel. The theory is the
Neuro-toxin in pufferfish puts people into a deathlike paralysis then they're dug
up and carried off to be slave labor somewhere.

The problem seems to be that while pufferfish is indeed a common ingrediate in
'Zombie powder' the samples provided either didn't contain any toxin or to little
to have any kind of effect. If this sample was standard that would mean that a
successful zombification would happen about once every blue moon when the sorceror
lucked out and not only got some toxin in his pufferfish but enough to paralyze.

The show also exhibited two people who were supposedly zombies; a man who seemed
normal and a woman who did not. No further examples have come forward in the
twenty odd years since these two appeared - which seems a bit odd unless a successful
zombie is as rare as the powder samples suggest.

Or maybe its all just folklore after all.....