High protein diets are likely popular because they do cause weight loss and allow us to eat all of those meats and cheeses that we love. Some examples of these diets include Atkins, Zone, and South Beach Diet.
A calorie is a unit, based on the measurement of energy provided by food. While we all need a certain number of calories per day, it is certain that all calories were not created equal.
In studying neurobiology, we learn that our behavior and perception stem from neurotransmitters, hormones, receptors, and synapses that constantly create senses and perceptions from information in our environment.