When thoughts about food tend to take over your day, other parts of life tend to suffer. Some persons spend large chunks of their days shopping for food, planning meals, avoiding meals, arranging to be near bathrooms so that purging will be easy, and so on.
When asked what they would be thinking about if they couldn't think about food, it is common for people with eating disorders to say, "I don't know." There is less interest in relationships, work, and outside interests. When food dominates life, it is easy to reinforce eating disorder behaviors.
