Calorie Burn is the total number of Calories you have “burned” over the course of a given day, tallied on short regular intervals. If you don’t take in enough Calories (by eating food) to meet or exceed your Calorie Burn, you will deplete your Calorie Store, and begin to lose health and endurance (Condition). You need to eat to survive, and if you don’t have enough food, you have to govern your energy carefully to make sure you can survive. Calorie burn increases when sprinting.
Note: Calories appear to burn faster if the player is outside in the cold with minimal protection, or has hypothermia. (unverified)