1. A tamper-resistant device that automatically monitors caloric intake comprising: one or more automatic-imaging members that are worn on one or more locations on a person from which these members: collectively and automatically take pictures of the person's mouth when the person eats and pictures of a reachable food source when the person eats; wherein a reachable food source is a food source that the person can reach by moving their arm; and wherein food can include liquid nourishment as well as solid food; a tamper-resisting mechanism which detects and responds if the operation of the one or more automatic-imaging members is impaired; and an image-analyzing member which automatically analyzes pictures of the person's mouth and pictures of the reachable food source in order to estimate the types and quantities of food that are consumed by the person.