"While most folks recognize the power of food to bring people together, I notice most its power to divide. Many religions enshrine various forms of commensalisms, or rules that govern with whom you can eat and with whom you
cannot. In Hinduism, high-caste persons can't eat in the presence of those who are low caste, whose very shadow defiles the former. Many religions specify not only the animals that can be eaten but the ways in which those animals must be killed as a precondition for eating them and the means by which they must be prepared. This can seriously limit the number of people one can eat with."
You can listen to the entire excerpt on NPR's website here.