This piece on cannibalism, by the exceptionally good Jenny Diski, is interesting (it's a review of An Intellectual History of Cannibalism by Catalin Avramescu, translated by Alistair Ian Blyth). Thought-provoking, too. One thought it provoked for me was whether there hasn't been a profound shift in the cultural logic of food.
Previously, the rationale was: 'I eat and internalise this food, thereby adding its strength to mine.' So, if you eat a strong warrior it makes your own war-strength greater (or, in less cannibalistic ages: eat beef to be strong as an ox; drink wine and the god enters into you). But now we increasingly view food as the enemy, as a kind of poison: if not literally so (the vogue for talking about 'toxins') then in terms of the attrition against our health: fat; sugars; cholesterol; junk. In such a culture the last thing you want to do is internalise the food; and anorexia becomes the norm. Or perhaps the logic shifts: eat beef to become fat and stupid as a cow and so on.