1. A tamper-resistant wearable device that automatically monitors caloric intake comprising: a motion sensor which is configured to be worn on the person's wrist; a camera which is configured to be worn on a person's wrist, wherein the field of view of this camera is automatically moved based on data from the motion sensor so that the camera automatically takes pictures of the person's mouth when the person eats and automatically takes 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, wherein this tamper-resisting mechanism detects when the camera is removed from the person's body, and wherein this tamper-resisting mechanism further detects when the field of view of this camera does not include the person's mouth when the person eats and/or a reachable food source when the person eats; and a computer 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.