If people weren't made to be eaten, why are they made out of meat?
Old joke... I'll eat anything that cant catch a frisbee.
Who says they weren't?
But of course, the serious answers are severalfold. First of all, the prohibition against murder prevents us from killing humans for food. Secondly, God affirms our natural aversion to the practice in several verses where he suggests that we will practice cannibalism in times of intense suffering.
And thirdly, we do practice cannibalism of a sort, through the Eucharist/Communion.