To quote from this article by Victor Benno Meyer-Rochow:
Food taboos are known from virtually all human societies. Most religions declare certain food items fit and others unfit for human consumption. Dietary rules and regulations may govern particular phases of the human life cycle and may be associated with special events such as menstrual period, pregnancy, childbirth, lactation, and – in traditional societies – preparation for the hunt, battle, wedding, funeral, etc. On a comparative basis many food taboos seem to make no sense at all, as to what may be declared unfit by one group may be perfectly acceptable to another. On the other hand, food taboos have a long history and one ought to expect a sound explanation for the existence (and persistence) of certain dietary customs in a given culture. Yet, this is a highly debated view and no single theory may explain why people employ special food taboos.
There seem to be as many different food and drink prohibitions as there are cultures. Perhaps some of the more familiar include Kosher foods, that conform to the regulations of kashrut, and Halal, which refers to what is permissible or lawful in traditional Islamic law. There are, however, plenty of others.
Those who wish to follow up this topic may be interested in the following articles:
- Food and Eating: An Anthropological Perspective
- Food taboos and oddities: Q&A with Brian Stross