When we look up the definitions of the words “hunger” and “appetite” in the dictionary, we’ll find they are more or less the same. One of the definitions of hunger in the Merriam-Webster OnLine Dictionary is, “an uneasy sensation occasioned by the lack of food,” while its foremost definition of appetite is, “the desire to eat.” Yet if we try to have a more thorough understanding of the human body’s machinery, particularly the functions of the alimentary canal, we’ll come to know that hunger and appetite are not entirely the same.
It is probably because scientific information about the specificity in food requirements (i.e., the determinate quality and quantity of food for the body’s sustenance) is so recent that the significance of hunger and appetite does not at all matter to most people. It is simply that the inherent sensations of hunger and appetite are man’s important guiding information in the choice and ingestion of food.
The difference between hunger and appetite is that the former is often accompanied by the latter, while a person may have appetite without necessarily feeling hungry. Hunger and appetite, for this purpose, have to be viewed from the scientific standpoint.
Like all sensations, hunger is difficult to describe. There are certain things about it though, that are recognizable. The first is in the nature of generalized weakness and uneasiness, related to no specific part of the body. The sensory nerve impulses emanating from the alimentary canal (the tubular channel that stretches from the mouth to the anus, and functions in the body processes of digestion, food absorption, and waste excretion) may have a lot to do with these conditions; it is also possible that these conditions are related to the diminished sugar content in the blood.
The other component is even more easily recognizable than the first, in as much as it involves more distinct sensations that are usually localized above the stomach or the upper portion of the abdomen. The sensations are characterized by brief piercing spasms of pain that occur at infrequent intervals; an occurrence may last for a few seconds, ceases, and then recurs in a few seconds to about a minute.
Proceeding along the dictionary’s definition of appetite, it is quite easy to understand why even after completely satisfying our hunger with a sumptuous meal, we still would like to go for a piece of the enticing dessert served at the table. To a large extent, appetite depends upon the pleasant experiences with food that are retained in one’s mind. But hunger is all too different in that it cannot be altered by any of the acquired experiences with food of the person.