Funny; this subject came up just as I was reading Martin Gardner's
latest book    "Did Adam and Eve Have Navels?"
from Skeptical Inquirer columns on dubious theories
like urine therapy, numerology and intelligent design
 -- and the chapter: Is cannibalism a myth?
 -- basically how anthropologists' claim
of the existence of cultures that consumed humans as a consistent
source of meat could be flimsy (it was always "that other tribe
that does it").

Fun reading.

Philip Thrift     "Paleofitness"        http://www.paleofitness.com