This idea has a medical basis, for research has shown there is a close correlation between the mouth and emotional desires. People who are anxious and depressed often chew on something out of desperation.
這種說法是有醫學根據的，根據研究，口腔與慾望有很深的關係，所以心情浮躁煩悶的人，常不由自主猛吃東西。