Cravings are always your body's way of telling you that you are missing important nutrients...what you crave is an available, familiar source.
Pica (craving non-foods, like clay or chalk or dirt) used to be common in cities where nutrition was poor (before refrigeration made farm-fresh produce available in cities), and now it is almost unheard of. Women then would have had a hard time getting enough trace minerals from the food available.
If you are craving super high-fat, high calorie foods (I knew one woman who was craving cheesecake) it's probably simply that you are not eating enough, so by the end of the day you're crazy for the biggest calorie load you can find in the smallest package.
at 9:57 PM on Oct. 1, 2009